Sorry but not a single manager in the world would think it's foolish and naive to bring on a kid at that stage. Managers have been doing that for decades in the CL to give them experience when in a comfortable lead. If you cant do that at 3-0 up when can you do it?
At least 2 of the goals were Gvardiol mistakes, the pass to McAtee with the players around him in the central defensive position was horrendous. For some reason we're panicking once the ball is in our half and we're under a bit of pressure and in the last couple of matches he seems to be the worst.
I think when we get the fully fit players back we'll be fine, Stones doesn't panic, Diaz doesn't panic, and some of the goals we've conceded have been half chances that normally wouldn't happen. I would put all three of their goals last night in that bracket but as we know more than most, when things are not going for you it's tough.