It is hard to say the latter is only theoretically harmed when the rising price was caused by retail FOMO (according to SEC report) and Robinhood managed the majority of retail orders....
From the SEC's POV, a single brokerage stopping buying still means there was an open market. Robinhood FOMOers used margin accounts and instant deposit feature to drive the price up until Robinhood could no longer afford the loans they were offering. Fidelity never stopped allowing buys because they could afford the settlement collateral.