For me, less spam, bots, recycled posts.

The biggest difference I’ve noticed is that while Reddit may have a lot of large active communities, I would rarely get a quality response if I posted a question or a discussion topic.

Here, I can post to a community that hasn’t had a new post in a few days, and within an hour I have several people offering help or discussion.

Reddit is far more active, but Lemmy users are far more helpful.

If you have an issue with the Reddit admins, you either suck it up or stop using Reddit. If you have an issue with the Lemmy admins, you can migrate to another instance and forget about the old admins.

Communities being smaller is a double-edged sword. Yes, it’s harder to find the content that you want, but it’s easier to be heard here. And it’s overall easier to have a meaningful conversation here, that doesn’t get flooded with sea lions, irrationals, or 11yos. (Note: I’m saying that it is easier, I’m not saying that everyone here is sensible or acts sensibly all the time.)

If you’re left-wing you’ll have an easier time discussing politics here. And if you want/need a safe space there are some good instances for you, like Beehaw or Blåhaj, in Reddit they’d be simply flooded with entitled newbies until the mods give up.

So TL;DR: unless you’re one of those “lol! lmao!” kids or a right-winger, Lemmy is quality while Reddit is quantity.

Lemmy vaguely feels like Reddit when it wasn’t really popular. When you could comment and it wouldn’t be buried under 10,000 others. Participation almost feels pointless there.

So far it seems to me like the troll instance here is much lower. There are definitely reddit-esque people here who will reply to comments by demanding that you refute their ludicrous misinterpretation of whatever you said. But overall I think there’s much less hostility.

The community is the main selling point for me. Further left than reddit. Fewer bots and recycled bot posts. Generally less defensive and aggressive posters, though the US election has made things a bit more contentious, I’m sure it’s still better than reddit on this.

I really like the UI a lot better than reddit. So far I’m finding the single-page app architecture works really smooth.

Free speach baby. Its an escape from corporate censorship.

Reddit:

• It has a much larger user base and many heavily specialized boards that nevertheless stay reasonably active.
• It’s a collection of echo chambers. Dissent is usually stomped out by mass downvoting and heavy moderation/bans. It’s rare to find a board that allows arguments for a long period of time. Agree with the board’s users/mods or get silenced. Posted rules do not matter, and you can definitely be hateful in ways that violate posted rules so long as that type of hate is acceptable on that board.
• So many users mean that getting content to succeed is a crapshoot. Often posts become lost in the noise, especially on busy boards.
• I left about a year ago, but apparently there’s a lot of bot/AI slop on boards now.

Lemmy:

• Much smaller user base. Heavily specialized boards move slowly if they exist at all. It’s not unusual to see boards where it’s just one/a few people posting with days in between new content.
• More ability to have disagreements. Whether it’s because moderating a smaller # of users is easier, the mods are less authoritarian, or whatever you are more likely to be able to disagree. Don’t be blatantly racist, celebrating violence, clearly trolling, etc. and you’ll probably remain able to participate. I’m sure this isn’t universal on all boards, but it’s my experience on many boards.
• For all that I believe the above point, there are still “echo chamber” moments on Lemmy. Sometimes it seems people may be downvoted simply because they are already downvoted. It’s still way less egregious than on Reddit, and such is human nature I suppose.
• Fewer users means you are more likely to get some engagement on your post, at least in my experience. I never sorted my feed by new posts on Reddit because it was an avalanche of posts of questionable quality, so I only saw whatever content had already succeeded. On Lemmy I can look for new posts and see most if not all content on the boards I enjoy.

Every post isn’t filled with the same exact joke repeated multiple times. That’s what really killed reddit for me.

Your first two bullet points are the same on both sites (both sites…hehe)

I actually think all the posts talking about the size of communities, amount of memes on the frontpage and so on are wrong, since those will naturally change over time and are not fixed.

Every platform will see changes in their user base to some degree. Reddit now is very different to Reddit 10 years ago. The same thing will happen to Lemmy: If growth continues we will see more engagement in niche communities, but also more low effort posts and reposts.

Considering it doesn’t do anything fundamentally different to reddit in the way of being a content aggregator with comment section it will be a similar experience. It would be different if it e.g. had a function to make older posts resurface and stay relevant longer to foster longer conversations, or structure comments differently since right now the further down a chain you go, the less people will engage with it.

Even if the average user doesn’t care about open source or federation, they’ll still benefit (and suffer) from the consequences.

On a centralised platform like Reddit you are beholden to their will for better or worse, and incentives might change over time such in their case with taking investor money and going public. This can have consequences such as forcing out third party software (one of the events that brought a lot of people here), but also censoring specific content or taking away powers from moderators.

There are downsides to it, since smaller, less professionally run instances might disappear at some point or have less reliability. But The upside is the option to choose and the resilience that should things change at one instance/community, you can switch without having to leave the whole ecosystem. And for that you do not have to be a moderator or volunteer

The existence of different instances also to some degree helps identify users to some degree, the obvious choice being political instances like hexbear.

The average user is not looking for NSFW

That’s an assumption i’ll challenge. Looking at the amount of porn on the internet, the average person most definitely is looking for it. But that is probably a bit offtopic.

Same shit, new boss

You can have more than one account on each instance, therefore if you get banned on one you can use your other one and still get the same content.