Some early PC software, mostly games, were written expecting the computer ran at a fixed speed which was the speed of the original IBM PC which used an Intel 8088 that ran at 4.77 MHz. If the IBM PC was more like computers such as the Commodore 64 which changed little during its production run, that would have been fine. But eventually faster PC's were released that ran on 286, 386, 486, etc. CPUs that were considerably faster and hence software that expected the original IBM PC hardware ran way too fast.

The turbo button was a bit of a misnomer since you would normally have it on and leave it on, only turning it off as sort of a compatibility mode to run older software. How effective it was varied quite a bit - some computers turning it off would get you pretty close to the original IBM PC in terms of speed, but others would just slow the computer down, but not nearly enough, making it mostly useless for what it was intended for.

Kind of, though it's about the CPU's clock speed rather than the details of the game.

So, pedantically? no.

Experientially? yes.