I immerse myself in the story and these things kick me out of my immersion. Also homophones, contractions, and incessant repetition of words. I understand English is not everyone's first language and I give a good amount of leeway for that.
Not capitalizing 'I' is obnoxious. It doesn't hurt the story, but it breaks my cadence and there are enough grammatically correct stories out there that I can happily drop one that doesn't bother to capitalize 'I'. Writers are free to ignore, of course, but the loss is only theirs. Nobody reads stories just because the author did not capitalize 'I', but more than a few readers certainly drop stories for that reason. To each their own, I suppose.
Same with homophones and contractions. I get that homophones are hard. English is a dumb language and is even worse as a second language. Homophones have different meanings. This can affect the story. At a minimum I have to make sure I understand what the author is trying to convey. This breaks immersion as well. I'll keep reading if the author is open to edit suggestions. If they're not interested in correcting when a person tries to help edit (politely, of course, I don't act like an asshole when suggesting edits, that's just a dick move) I consider it a sign they're less interested in quality than quantity and I'm happy to move on to quality.
I hope that writers care about quality. Beggars can't be choosers, but it's a beggar's market right now. Caring about quality can only increase your readership numbers. If that's at all important to a writer, I suggest at least taking friendly editing advice from readers.
