With a bot, I figured there was no hope of bidding 7H intelligently In fact, my feeling is that (among all hands partner might hold) 6H will go down more than 7H will make. On his actual hand, even though you did go down only because clubs were 5-2, but you really needed far more than that.
So at minimum you need clubs 4-3. If all that works, you still need trumps 2-2 to make 7 hearts, because after ruffing 2 clubs you have only the J left, so you’ll lose if someone has Qxx or a stiff Q. (Double dummy you could pick up Qxx onside if LHO’s stiff were the 10.)
But as you say, the actual hand proves nothing. Many hands will make 7H. Many hands won’t. My thinking was that whenever partner has 3 clubs without the Q, you don’t want to be in 7. At best he has J10 of clubs, but then you’re on a finesse.
Also, you may well have a trump loser. Even if he has Qxx, you do if trumps are 4-0, and if he has four hearts without the Q you might need trumps 2-1. (Though with J10xx in dummy you could pick up 3-0 onside.)