I remember Apple IIe’s having 5.25 floppies when they first arrived. 3.5s became common later (boy, did we think 1.44MB was just the cat’s meow! LOL).
IBM compatible became standard because of the open architecture, which made competition for hardware monies a way for the business managers to save a few dimes.
JMHO, of course - I am not a tech historian. I’m just an aging engineer in the aerospace computing industry! LOL
The 1.44mb 3.5 floppies didn’t become standard on the Apple II, those were 800K. 1.44mb came along on the Mac (which had 800K floppies by then) only after it took over the PC market; some third-party Apple II drives supported the 400k (single sided, original Mac style), 720K, 800K, 1440K, and 1600K capacities.