Agree with you there. I still differentiate between country and pop etc as although it's become very popular in the US and Canada, outside of their country music is definitely in the minority. (It shouldn't be, there's some really great country tracks).

Pop music these days has started to drift more into RnB elements. Take Ariana Grande as an example, she's definitely a pop artist, but there's a lot of RnB elements in her stuff.

Lots of Rock elements get used in some pop artist stuff hell even, dangerous woman contained a guitar solo 🤣.

As for folk, I do feel like what we'd traditionally recognise as folk music is pretty much just country music from a specific culture. Ed Sheerans - Gallway Girl pulls Irish folk elements but it's fundamentally a pop song.

So I definitely agree that country music is very closely aligned with pop and uses lots of other genres elements. Some country takes rap and hip hop styles and incorporates those. I've even heard some country music with screamo vocal parts.

Very versatile genre.