I've been away from poker for a while and am getting back in to the game.
I've been reading how good GTO Wizard is, so i'm trying it out.

On the very first test it gives me a 6 max tourney. All players 200bb Hero in hijack.
These are the correct moves according to GTO Wizard:

UTG folds.
Hero raises 2.5bb
3 folds and BB calls

FLOP: K2, Qh, 8d

BB Check, Hero Check

Turn: 3d

BB Check, Hero Check

River: 2h

BB Bet 2bb, Hero Fold

I would be representing a hand a lot here against most standard opponents.
The KQ surely hits Heros range much more than the player in BB.

Are they assuming that the BB only calls with the top of his range here?f

I feel it should be the bb in fear of the cbet from the hijack on this fop texture.

We could fold out under pairs and floats with bets on the flop and turn. Only Kings, Queens, Straight draws, and backdoor flushes would stay on the flop. Only diamond FD stay on the turn. Any missed draws fold the river.
I would also bet any river that misses the straight or flush draws. By the river we would even get some Q and K with bad kicker hands folding.

Maybe I'm completely wrong but at 200bb deep, why even raise A10os hand pf if your just going to give up if it doesn't hit.

I forgot to put the Hero starting hand.
Ad 10h

I assumed "K2" is Ks.
Bets are a bit different (2 BB preflop and 2.5 BB on the river, instead of 2.5 BB preflop and 2 BB on the river).
Kind of found the same thing with another solver. It's heads' up though but similar enough.

It would call 1/3 of the time with AT, probably for defense, but mostly place the opponent on a pair of 8.

I think the solver is using a big bet or check strategy OTF. This is because HJ has the nut advantage and BB has a lot of middling hands with good equity. For example any hand with two cards that are 8 or higher can easily call a small bet, except maybe A9. So it makes sense to size up to put BB in a tough spot.

So if the solver bets big they can't bet everything, and AT makes sense to check in that context.

OTT you now have good showdown value against a weak range, so normal check.

I'm a bit surprised if ATo is 100% fold OTR but I would think it's pretty indifferent.