Qatar's bid is itself all about Qatar. Nothing else. They want United in their portfolio because they're good PR for their dictatorship.
When this is understood (not 'accepted' as it's not an opinion) you soon see 'morality' and indeed 'the politics' are core arguments, and should be directly in the forefront of how this takeover is received.
Noted, however it's not a simple as that.
If you use your argument then that would apply to all investments made by those entities.
Clearly the UK government, and Western governments in general, have a different standard.
Unfortunately, whether we like it or not, those of the standards that are going to be applied and not our own.
During the financial crisis Barclays Bank were bailed out by a combination of those emirates. The UK government were more than happy to give it the go-ahead because it saved the British taxpayer literally billions of pounds when the UK government was struggling to bailout other institutions.
Now it would be bazaar, to the extreme, if they now decide that Qatar are no longer a good egg.
However I appreciate that some people are against the bid, for good reason, however unless you start a campaign and convince the British government that your moral stance should be acknowledged by the country as a whole then unfortunately, with respect, you won't get very far.
You could argue that as United fans we should universally make a stand against state ownership, however given how poorly fans are regarded, the Glazer fiasco being a prime example, I would conclude that the chances of anyone "important" listening are negligible.
The Glazers messed up one club because of incompetence. Nations getting invested into football ruin the competitive integrity of the whole sport long-term. Manchester City dominating world football at the moment is down to both smart decision-making and an unlimited amount of money to build something up over 15 years. And they likely cheated their way to it.
Look at it from this perspective: What's the point of a club like Brighton (that has come such a long way in the last 14 years by playing it smart), if long-term the top 3 spots in the PL will be pre-occupied by City, United and Newcastle? Or will eventually every club be begging for a state to save them?
What's the point of Spurs and Atletico Madrid? Both of them made huge progress to get to where they are now since the early 2000s.
Ok, however if your argument is that these countries/persons are "causing" a cancer in football due to their "doping" then that is a different argument.
Since the 1970s only Brian Clough's Derby and Forest, Bobby Robson's Ipswich had been examples of smaller clubs making an impact. The others have been either sleeping giants or giant football clubs, Jack Walker's Blackburn and Leicester were financially helped.
So the plight of Brighton is nothing new.
There is no way that there will ever be financial parity, just look at Real, Barcelona, Juventus or Bayern, 'established' old clubs that don't give a sh. t.