I don't see any basis for a suit against MQA. It looks like the company is going through what in the US would be Chapter 11 bankruptcy, which is really not that big of a deal. As long as MQA has a revenue stream, it's likely some entity will buy it. It won't matter to me if I'm wrong because I have no plans for MQA in my system.
Tidal class-action
MQA declared bankruptcy. I smell the fear of a class action lawsuit against Tidal. We could do that. Tidal has 8 million subscribers, we don't know how many or how long they all were paying double by subscribing to the 'nobody can prove Tidal has any tracks higher than 44.1khz' plan. They probably have lots of people on phones who haven't even heard of MQA who trust them and wanted the one that sounds better. They're right not to have to listen to any talk about MQA if they want the plan that sounds better.
MQA means you can't prove the file is an original copy or not. That Beethoven track you like it says is 192 could actually be Dua Lipa at 11khz.
The bankruptcy move was probably to protect themselves from Tidal, who is the receiver of people's funds.