I type just as fast on the butterfly mechanism as any other, a consistent 90wpm with no mistakes and scattershot up to about 130 wpm during programming. I've been at this speed for about 2 decades now, going all the way back to using a vintage model M keyboard, an AEII keyboard, etc.
I sometimes go back and forth between my newer MBPs and a 2014 I still have. It takes about an hour of adjustment to get my speed up when switching.