If you’re getting 650 Mbps, all of your hardware is definitely capable of running 1 Gbps
Just to clarify, this means there aren’t any 100 Mbps bottlenecks, not that the hardware can run at 1 Gbps. When Gigabit was new, a lot of hardware was rated for Gigabit but couldn’t actually get 1000Mbps. I know this is less of an issue now Gigabit is mature, but there’s still a possibility something is bottlenecking just due to the hardware not being able to keep up.
There are levels of bad. Don’t let perfect be the enemy of good (or in this case, only slightly better).