I think I've made it clear by now that I'm not really expecting a Monster Hunter fighter in general and I am not at all convinced about the arguments for it/the counters to arguments against it.
For one, the fact Ultimate went by with not only adding Rathalos as a boss, not only adding Rathalos as an Assist, not only having music tracks on top of that in the base game, but going back to re-add the Mii Costumes from Smash For AND a new hat for Felyne in the DLC, as well as adding a Spirit Event for Rise and a promotional Spirit for Stories 2, and not even so much as a peep about having a fighter by the end of DLC? That comes off as incredibly damning to me. As far as I'm concerned it should have already happened in Ultimate if it was going to happen, if Monster Hunter was already considered a big enough deal to have notable representation.
No amount of "oh, but it's only because they prioritized other series

" when they still found it enough of a priority for a BOSS with associated tracks and then going back to expand representation through DLC, or "oh, but Monster Hunter wasn't as big as it is now

" when it was already Capcom's 3rd biggest seller by the time of the project proposal in December of 2015 and it overtook Street Fighter as their 2nd by the end of March of 2017, well before DLC was ever a factor, is going to sway me on this.
And
then there's the Hunter itself. The whole reason for this topic over the idea of the Hunter being a fighter.
I have absolutely no reason to believe a Hunter specifically in the cards.
While people are quick to point out how we only had a specific denial for Ultimate Marvel vs. Capcom 3 that was "null" because of Marvel vs. Capcom Infinite, this isn't the "gotcha" moment they hope it is.
Infinite is still literally to this day the only collaboration that features Monster Hunter with an actual original Hunter. All other collaborations feature only the Monsters (usually prioritizing Rathalos) or the armors for other characters to wear. All the ones before Infinite and all the ones since.
Including Smash itself twice.
Quite literally the only human character that is represented in Smash from the franchise is the Rider from Stories 2. And that's only because he's riding the Razewing Ratha that the Spirit is representing.
A Hunter isn't even an Assist, to which they awkwardly had Rathalos perform double duty for, nor is a Hunter a
SPIRIT even with the Rise event when they had plenty of renders to work with along the Palamute and Palico.
But instead once again, the Monsters were focused on and the Hunters left out. Which feels very deliberate. And quite frankly? I don't see this changing for the next Smash. Even if Monster Hunter gets a fighter, there is more reason to believe it's going to be a Monster (especially some type of Rathalos) or a Felyne since they've also been playable within the franchise and use weapons not unlike the Hunters themselves. But there's also the possibility Monster Hunter just continues to not get a fighter and all representation be it boss, Assist, collectible, etc. is all Monsters (or armors for Miis) whether people like it or not.
But that's just me, and it's something I've needed to get off my chest.