That's just it though, Robin hood didn't delist gamestop. They just decided arbitrarily that their users are only allowed to sell it. Coincidentally, this is a move that highly benefits a major partner of theirs.
That connection is like 3 degrees of separation at best, though. Robinhood sells order flow to a number of market makers, one of which is Citadel Securities [1]. Citadel Securities is part of the Citadel group, which consists of a hedge fund (Citadel LLC) and a market making firm (Citadel Securities LLC) [2]. While both companies are owned by Ken Griffin and share many resources, they are split by a "Chinese Wall" [3] to prevent any conflict of interest between both sides of the firm. They also have different CEOs, management, employees, infrastructure, etc. as a result of this. Now, Citadel (the hedge fund) has invested $2 billion into Melvin Capital, which is one of the firms central to the whole issue [4]. Yet Melvin Capital has already closed its position in GME [5], which means that they no longer have a vested interest in the performance of GME.
There are several glaring problems with the theory that Citadel is pushing for Robinhood to ban buying GME for financial motives:
1. Robinhood has NO relationship with Citadel LLC
2. Everybody knows about the theoretical conflict of interest between Citadel/Citadel Securities so it is incredibly unlikely that Citadel Securities would risk doing anything to help Citadel in such a high profile scenario (i.e. the SEC/FINRA would be able to find out this kind of thing very quickly and very easily)
3. Citadel has no financial motive to stop trading of GME, because Melvin Capital has no financial motive to stop trading of GME
4. If it was as simple as trying to profit off of GME going down, why would they bother halting trades on other securities (AMC, BB, NOK, BBBY, etc.)?
This article does a really good job at explaining the situation (much better than I can do) [6]
Since the claim that they closed their position in itself would potentially influence the market to their benefit, I don't see a reason to trust their statement.
Either way, it would be illegal to say that they closed their position for the sake of influencing the market. The SEC really doesn't play around with that type of thing in such a high profile case
Because they risk running of being short squeezed in those stocks as well? Last time I check, big money isn't exactly throwing itself at airlines, mobile areas other than Android or iOS, and cinemas, even though two of those are bound to pick up later this year once covid is over and Black Berry is in talks with Baidu, which you can't ignore.
The big guys know all this, only they were hoping to short, make a profit, and then reinvest down the road when things picked back up, making even more money. WSB just capitalized on their strategy and now that they are losing, they are throwing a fit.