We've faced similar issues to what we saw against Norwich (concerns about technical ability/the fitness of the squad, players routinely failing to do the basics and struggling to dominate lesser teams) for about 10 years now so I'm not convinced it's a problem started by Ole. We can't see what goes on behind the scenes and much of the argument in here is just people parroting the bits of unsubstantiated gossip which back their viewpoint and disregarding the rest. All that's really clear is that Ole never consistently had us playing brilliantly, that by the time he'd left we were consistently playing very poorly and that after 3 games Ralf hasn't got us playing well again.
Which isn't to say there are no right and wrong answers - we can use the evidence we have to make educated guesses, but people are so desperate to attribute every failing to whatever (or usually, whoever) they've decided is The Main Problem, that they feign certainty about things we really don't have a clue about. On the basis of the evidence I can conclude Ole wasn't good enough to be United manager and put together a decent argument as to why I think that, but in doing so I don't feel the need to selectively cobble together a bunch of speculation to justify taking that argument to a cartoonish extreme in lieu of accepting that there can be more than one issue at once. The pretence that Ole was 100% dreadful and was personally running round offering aging/injury prone squad players new contracts and coaching our players' ability to control or pass a ball out of them is tiresome, as is the pretence that Ole wasn't a problem at all. What's more tiresome though, is that the United forum is now just two groups of people holding those extreme positions arguing that every scrap of news is further evidence that their chosen viewpoint was right (e.g - we play badly against Norwich and one side jumps to shout that it's evidence Ole wasn't the problem whilst the other jumps to shout that actually, it's evidence that Ole has ruined the club so deeply even a great new manager can't save it).