If you have a good router that does some queue management and doesn’t suffer from buffer bloat, it shouldn’t impact it too much.
> Due to traffic management demands, speeds are limited to around 350Mbps, so if on fiber or high-speed cable, that's the measurable limit.
https://evenroute.com/iqrouter#:~:text=ensure%20low%20latenc...
If you don't mind doing a little work a Pi 4 will do cake at gig.