I would put all the blame on Ten Hag because he is the only coach that has used a huge amount of money to buy players above their value which is affecting the club performance and financial state. All most all the players he bought are all average players who cannot withstand the pressure in the EPL competition. United bought the wrong players and expected a magic or what.
I won’t blame Ten hag entirely for Manchester United poor performance, Ten hag spent huge amount of money signing players, he signed players which he think will improve Manchester United performance, but he ended up signing the wrong set of players, most of the players he signed were performing well in their previous clubs that they played for, but immediately they joined Manchester United, things changed, they started performing poorly, and Manchester United performance has been getting worst.
What Manchester United should do now is to sell some players thats not really useful to them, and then sign new players, if Manchester United performance doesn’t improve after signing new players, then I will say Manchester United problem is not from players.