This just underscores what a complete shambles we are on all levels on and off the pitch under these parsitic owners.
I am fully aware about the unpopularity of the Glazers. However, I don't think their "parasitic" behavior is the reason of United struggles. Focusing on the owners is actually preventing you to address the clubs real problems.
At the end it doesn't matter for the players or silverware, whether the club is debt free, got 50 millions of 500 millions £ of debt. Barcelona or Real Madrid are still successful despite being heavily indebted for many years
After all Man United's investments into the team is only second to Man City. The Glazer's definitely haven't been cheapskates when it comes to pouring money into the team.
Your problems aren't missing investment but the lack of a long-term vision and philosophy how Man United should play. Going for big name players regardless whether they fit into the team or not. Hiring coaches with complete different often opposite playing philosophies, which not only prevented any consistency and development of a playing identity but left you with a squad of players that doesn't really suit any game style.
Hearing your ex players like Keane, Scholes or Rio to recommend hiring Simone as the new coach makes me cringe. Not only would the football be the total opposite of the Man United way under Ferguson but you also don't have the players who would thrive under Simone.
In short the Glazer's taking money out of the club is surely one of your lesser issues.