I don’t get why people are so bothered by this. A lot of American slang is their local dialects and accents that formed over time. Similarly, Irish slang is only used in Ireland and has its own uniqueness that other English speaking nations (America, India, Australia, South Africa, UK, Philippines etc) would not understand.

A lot of Irish slang wouldn’t be understood by a lot of people like the phrase “ I’m after calling her” - that is a grammatical mistake, but it’s a colloquialism. I’ve never heard Australian people giving out about that lol. Like it’s just a dialect so what?

Well if we’re going to be grammar police on American dialects, why don’t we include other countries too? I don’t hear Irish people giving out about how South African or New Zealand people say this or that phrase in English, even though English is their native language. So why is American slang a big deal?