I haven't seen the game so can't comment on that, but some general thoughts spring to mind (massive waffle coming I'm afraid):
As people have mentioned above Exeter and ourselves had the shortest break and both are under performing. It is also a strange season and that is clearly affecting teams across sports - Liverpool are having a nightmare season, Tottenham aren't firing, meanwhile West Ham and 'lesser' teams are prospering. Also we are seeing teams dipping more in form than usual - Liverpool, even Man City before their latest run, Exeter in our sport. I don't think anyone can predict what effect lockdowns and bubbles have one individual players (especially those a long way from home), but as a whole it must be disruptive.
Then looking at individuals; young players always peak and fall more than experienced players as they have less to draw on when it goes wrong and when your senior players are also struggling it compounds those problems. Also, these youngsters have probably never been 'worked out' before - maybe on a match to match basis, but probably not with the analysis that goes on in the professional game. I wonder if we have a number of players where this is happening at the same time, without the luxury of being able to take them out and fix the issues.
Finally, I would bet good money we have players playing who wouldn't be if we had a full squad fit. The one that puzzles me is Minozzi as he pulled out of the Italy squad due to the pressures of bubbles etc. I was really surprised he came straight back in as I expected him to have some time to get his head straight.
I think we have a perfect storm that is impacting everything, in normal times players would be given time to get away but right now they don't have that option so they have fewer possibilities to reset. It's a difficult one and not easy to resolve, as Jurgen Klopp is finding out too.