You are grossly misinformed. Klopp doesn't have free reign (transfer committee), no Madrid/Barca/Bayern manager will ever have free reign, I don't even think Pep has as much free reign as you think he does. Only difference is City can afford to buy almost any player. Let's not make up facts to fit our own narratives.
He sabatoged himself. He was trusted with 400M+ and Alexis Sanchez and he was still 19 points off 1st. No sane CEO will give him more. This is the same manager who claimed the was his team and they could challenge for a title.
You just want to believe what you want believe facts be damned.
£400m is nothing when 2 of the players that was bought for him gulped more than 40% of that amount.
The team he inherited needed at least £800m to compete. The lack of squad investment in the twilight of Fergie's era contributed partially to this problem.
Before taking the job, United had finished 7th, 4th and 5th. Even before Pep arrived, United were several tiers below the top teams in the Premier League.
Klopp has a free rein. He bought Karius and he was allowed to replace with Alisson(£65m), he brought in Matip, Klavan and he was allowed to replace them with Van Dijk(£75m). Jose was given 2 rookies(Lindelof and Bailly) and when they fell short of the required standard, he was told to coach them into Maldini - some backing, that!
Another thing is......backing doesn't have to be in financial terms alone. Everyone at Liverpool knows Klopp is the man. It's his way or the highway. Same as Pep. At United, Mourinho says one thing to the players and they run to Woodward who always favoured the commercial value of the players over a manager that has won 25 trophies.
Jose Mourinho asked for Toby Alderweireld and he was told he's not as good as Jones/Smalling. Lo and behold, Toby will be playing in UCL final while the United world class centre backs aren't even good enough to make the average England squad recently assembled by Southgate.