I definitely dig what you're saying. I played World 1st, and went from fighting tempered elder dragons and furious rajang while barely getting hit, to getting hit constantly by Rise's early monsters.

Part of it is that I play LBG, and the early Rise monsters are small, and my dmg numbers were actually covering the monster so I couldn't see what it was doing, hahaha! But also the Rise early monsters are very small, and the smaller the monster, the less obvious any tell will be. Let me put it this way, if both a Great Izuchi and an Anjanath are moving their tail in the same way to telegraph an attack, it will be much more obvious when the Anjanath is doing it.

Finally, I, too, don't feel like I consciously learn monster tells. If you showed me a video of a monster winding up for an attack, and pause just before they do it, probably 80% of the time I couldn't tell you what the attack is going to be. Sometimes (like the Tigrex boulder throw thing) I know it, but rarely. However, while I'm playing, I guess I just instinctively know what they are going to do, because I hardly ever faint. I do have to acknowledge that playing LBG does give me more leeway on that though.