From what they’ve shown, Mirage won’t really have that grind, since it’s not an RPG game, nor is it as big as the last three games.

I guess it can be different for different people. Maybe I just never reached that “endgame point” but my progress was always marked by custom dialog and new quests in Odyssey, even if that sometimes meant a side quest rather than main quest.

The term ‘grind’ can be either a positive or negative depending on how much someone likes the core game loop. For something like Monster Hunter, it’s used in an appreciative way.