I think you and I have very different experiences. I rarely see that kind of correction if ever.

When you’re in a public space you never know when your words are being consumed by an ESL speaker. I think the best approach is natural yet accurate. They’re going to encounter contractions when dealing with native speakers, but the difference between it’s and its, for example, can be tricky so try to use them as taught.

Spelling mistakes can absolutely be an issue. It’s already hard enough to figure out English spelling without native speakers making it worse. Add on to that the difficulty in any added language of working out near homophones, let alone actual homophones.

I knew someone who was pretty decent with English as their third language but had trouble keeping Texas and taxes straight. I know another guy who is American and uses no in place of know. That one threw me for a while before I figured out what he was trying to say.

I will admit, I do like that “technically” the plural for octopus is “supposed to be” octopods (pronounced like oc-tip-o-dees) but that’s a fun “fact”, not a correction I’ve ever tried to make.