Games that came on floppy disks are usually "classic" ones, that are banging the hardware directly and somewhat assume the same standard Amiga equipped with 1 Meg of RAM only.
Most of these games are coded with dirty tricks to speed up performance which in todays day and age do not work on faster CPUs, like the 030 or 040 or 060 - and the Pistorm too, which behaves lke a really fast 040.
That's why most games are installed onto the hard disk (or SSD) and are executed through an compatibility layer called WHDLoad.