yes there being low end android phones is one of the few reasons.

i dont think that i need to care about how many other people use the same os as me?

which ‘more options’ does android have which the average user cares about? i use a custom launcher and sideloaded apps but the average user def doesnt care about those two

since the youtube app is preinstalled on most android based phones and it has +10 billion downloads, its safe to assume that theres around 10 billion android based devices sold. i looked at the first 16 results when searching for a launcher on the play store and added their downloads to get 441,76 million. remember that the actual number of people interested is wayyy lower. i alone am like 5 of those downloads on just my current. but even if we use 441,76 million out of 10 billion, thatd be < 4.5% of people caring at all about launchers. thats not even the average android user caring about launchers

even less people care about sideloading, the most popular apk i know of is newpipe, which has 26k github stars.

or did you mean other more options which i forgot about? afaik iOS caught up on most customiseability stuff in the last few versions