He’s got almost a new starting 11 of his choice, he’s got new owners and knowledgeable people above him, he’s had more time in the job than can reasonably be expected.
Has he been backed on the transfer market?
I won't say he hasn't been, because that wouldn't be true, but at the same time, I feel like the most vehement ten Hag outers are just simply not willing to contextualize anything about the recruitment under ETH, and will just say "600m spent", and it's case closed for them.
However:
Martínez basically missed more than a full season worth of games by now.
Malacia hasn't played since the 2022/23 season.
Mount has barely played.
Antony shouldn't have been okayed by ten Hag at such a ridiculous fee, but the Glazers shouldn't have interfered with our recruitment either and shouldn't have been willing to pay 3 times the player's real market value to Ajax. ETH is somewhat at fault for this, but it's far from solely being his fault.
Casemiro is another player he arguably shouldn't have accepted, but once again, what was the club thinking? Especially when according to the Athletic, they knew signing him meant no Kane or Rice next summer?
Why did the club tell him it was okay to send Reguilón back to Spurs, as Malacia and Shaw would be returning for the second half of last season?
Yoro hasn't played.
De Ligt, Zirkzee, Ugarte and Mazraoui have just started their United careers.
There's an argument to be made that the only signings ten Hag has managed to regularly use so far are Eriksen, Hojlund, Amrabat, and Onana, but the two Danes have also missed a considerable amount of games due to injury. That's not to say the tactical setup has been optimal, and that with everyone available, we are as good as we should be, but still. 5 players are new and haven't played much (or at all, in Yoro's case), and at least 3 players have missed an unbelieveable amount of games in Malacia, Mount, and Martínez. That's at least 8 signings
However, he can be criticized for Onana and Amrabat.
Why did he buy a technical goalkeeper, just for him to move to an approach that totally concedes control and possession, and goes vertical as soon as it's possible when his team wins the ball?
Why did he buy a double-pivot defensive midfielder, only for him to be used at left-back or as a lone #6, and only get like 5 games as a double-pivot DM all season? It's not a coincidence that Amrabat's best games came in those 5 games as well.
So it has been a mess. Awful decisions from the club as well, ten Hag okaying some of those awful decisions, misusing the players he signed, misusing some of the players he already had at his disposal IMO, etc.
Imagine what would've happened if Rashford doesn't have a great season in 22/23, or that we don't have a Mainoo or Garnacho in the youth ranks?
Overall, the ambition to back him was definitely there from the moment he was appointed, and under both the Glazers and Ineos so far, but he hasn't exactly had a good squad, full of his own players available, up until arguably now, because now we have good squad depth and just a few injuries, so the improvement has to happen very soon.