"And the fact that at that point they weren't even floppy anymore. Like 5 or 8 inch were..." No, they were all floppy. You are just thinking of the hard plast

"And the fact that at that point they weren't even floppy anymore. Like 5 or 8 inch were..." No, they were all floppy. You are just thinking of the hard plastic case that 3.5" diskettes had. If you crack it open and disassemble it, the actual spinning disk is just as floppy as the 5.25" was. This is as opposed to a "hard" disk which is a hard platter inside a fixed disk.