For casual adult playing though, I'd never reach" high level" playing. All I want is to play easy songs I like (I'm sure there are plenty of people like me), for which I think an automatic algorithm is pretty likely to work.
(Pianist here) But there is no objectively correct fingering, it's just what feels best/easiest/smoothest for you, personally. Having to read the fingering as well as the notes just seems to make it more complicated.
Even for the simplest music, say a C major triad chord in the right hand - C-E-G - you could play it 1-3-5, 1-2-4, 1-2-3, 2-3-5 etc. I have big hands, so 1-3-5 feels the least comfortable of those, although it may be the 'automatic' choice. I agree with what others have said, that learning scales and arpeggios teaches you almost all you need to know about sensible fingerings on piano, and then having fingering pre-written on any music is entirely unnecessary. Books of scales and arpeggios have fingering written in, which you should learn.
The automatic algorithm can definitely take hand size into account.
I often feel that the fingering I come up with myself as a beginner is suboptimal. What I usually do is to watch youtube videos repeatedly to study what experts do. And that really helps me correct some bad adhoc fingering. I'm sure it's an experience thing - I can totally understand why experts would consider fingering on a sheet as useless. But for beginners it can make a huge difference. You probably don't care about beginners. But that is a huge market with strong needs unsatisfied (besides auto-fingering, auto-transcription of popular songs is another one).
My second paragraph was about beginners and what seems to me their best course, not sure why you say that. (TAB for guitarist beginners similarly "can make a huge difference" I'm sure, but also it keeps you a beginner.) It seems you ignored what I said about scales and arpeggios. I wrote my previous comment because it seemed you similarly ignored what the person you replied to said before. But sure, whatever works for you. Good luck!
Didn't intend any offense. But let me introduce more about myself, and tons of other adult piano beginners. You can see if you really care.
I care absolutely nothing about piano basics. I have a busy full-time job and tons of side projects so I have absolutely no patience for learning boring basics. I paid hundreds of buck for piano lessons in college but I ended up going to only two lessons (again - busy!). Yeah I know it would possibly develop bad habits, but as long as I can play pieces I like, why would I care? I just want the thing that would satisfy my short-term needs. I know that spending some time training my basics would make me a better player, but this boringness is going to let me give up on piano entirely.
Again, no offense intended - just trying to describe a unique persona. So no need to educate me on practicing the basics - I have had enough of those from many people...
For casual adult playing though, I'd never reach" high level" playing. All I want is to play easy songs I like (I'm sure there are plenty of people like me), for which I think an automatic algorithm is pretty likely to work.