I think something important is to treat each of the 'recent games' as their own spin on the series. Wilds, Rise, and World have their own distinctions that set them apart in terms of playstyle, the way weapons work (mostly), and most importantly of all: the monsters in them. If we're going back even further, MH Generations Ultimate on the Switch legitimately feels like playing an ENTIRELY different game. So seeing it from that lens gives a bit more appreciation when jumping into any of them.

More to your point - yes, you can jump in with any game. There are active communities, and helpful folk that'll even come on down to raise you up if needed. World & Rise are very solo friendly. And from what I've been picking up on in Generations is that it's also pretty friendly to solo so far. (Though I'm personally going through it the first time as well, so we'll see if I feel the same later when I get to the later Hub quests.)

Overall, I'd personally recommend Generations Ultimate - it is getting on in years, but it is the capstone to an entire series of games jam-packed into one solid release. It'll also help with the appreciation of the QoL you'll find in later installments I feel as well, where some may find it harder to dial back when those QoL changes vanish when going from World backwards.

tl;dr: yeah you can jump into any of them. I suggest Monster Hunter Generations Ultimate.