Our 286 (which was the first computer my family owned) also had a 40MB Hard Disk, which seemed like plenty at the time. It could run Windows 3.1 with that, although it wasn't exactly fast.
I scrounged enough chips and a carrier board to max my Compaq out at 3.6MB. That may have been a model specific limitation.
I believe that this computer had a 20MB hard drive, and that I eventually ran Stacker to compress the volume and squeeze out a bit more space. I know for sure that I never got anywhere close to 100MB.
On one of my computers in this era, I managed to get a paperwhite VGA and Windows 3.11 (for workgroups) running despite not meeting product specs. My 40-something brain is not quite reliable enough for me to state this with any certainty.
Our 286 (which was the first computer my family owned) also had a 40MB Hard Disk, which seemed like plenty at the time. It could run Windows 3.1 with that, although it wasn't exactly fast.