That is more whom not to sign (as a gesture of goodwill of his previous clubs, not whom to sign).
Nevertheless, he is Pep Guardiola, arguably the best manager of all time. Not everyone should have the same power as him. Lio Messi also choose some players that Barca should sign, which they did, it does not mean that Antony should get the same power as Messi had at Barca.
Nonsense. Proof a manager has input into who a club signs and does not sign and you’d rather shift goalposts than deliver substantive proof of your own knowledge as to how a football club is run.