Interrupt doesn't work

[halofreak1990]

The function call @Technoguy posted looks suspiciously like the one from http://www.brokenthorn.com/Resources/OSDev20.html

If ATA/SATA/AHCI/USB are not difficult, then a floppy driver is easier too, so why not implement it?

The fact is that floppies are still capable to make things easier, and are actually vital if you use old ISA machines trying to make sure that you're dealing only with code that runs natively in the best minimum or maximum i386 (386DX/387) as the absolute minimum platform for your base system and toolchain when compiled/built.

Because floppies are old technology. Few people (if any) still use them today. I think we should try to keep up with modern hardware, not backwards-compatibility with old hardware.
And I didn't say USB is easy; I know it's difficult, but unlike floppy drives, coding a USB driver will be worth the effort.

Writing a floppy driver that works both on real hardware and in emulators can be quite a challenge. That in itself can be a reason to write one. Also, if you're still in the process of learning OSDev and/or driver development, writing a floppy driver can be just as valuable an experience as writing a USB driver, with the former being easier to implement as it's a relatively simple setup.