Uhh okay? That doesnt rly have anything to do with using hotkeys
Hotkeys are just easier, less work for the player
Hotkeys are quite literally a game changer, I guess no one could seriously deny that. You may be able to play the game and use all features just fine going mouse only (a.k.a. one-armed), but there's no doubt that this will severely limit your apm ceiling. From my experience, once you get used to using hotkeys or even keyboard scrolling there's just no way back.
The main thing many people seem to struggle with to varying degree is, however, being able to use the keyboard properly in the first place. If you're struggling to find or hit the right keys without having to take your eyes off the screen then relying on hotkeys can be more of a nuisance than an actual help. It takes quite a bit of effort to build the necessary muscle memory to overcome this, which is probably why many people simply don't bother.
Luckily (also for me, since I'm quite bad at using a keyboard properly myself) there are ways to make things a bit easier, such as switching to the more accessible grid key layout or binding certain keys your mouse. I can only encourage any "mouse-only" players out there to at least give it a try, from my experience it's absolutely worth it.
Or, like the OP apparently, keep dismissing hotkeys as something for the basement-dwelling, no-life part of the playerbase and forever play with one hand tied behind your back.