

The EU can and should force Steam to get rid of the MFN clause. All Valve needs to do is to let competing stores price games cheaper than on Steam. (So long as Steam services are not involved with that off-Steam purchase.)
There’s still plenty of benefits Steam provides to customers that many may choose it over a different store even if they could get the game for cheaper. And Steam also provides developers with tools that make Steam worth it, like Steam networking and cloud saves. As Gabe Newell famously said about piracy, but I believe this applies in this case too, it’s simply a service problem.
To add to what you’re saying: To be fair, most of the lawsuit I don’t really agree with, but maybe it’s just laying it on thick.
Part of the argument is them trying to separate the Steam “Store” from the Steam “Gaming Platform”, and in many ways that’s obviously not possible. But they say that because of Steam’s monopolistic-ish position, publishers can’t not be on the “gaming platform”, because it’s where most people want their games, or else they’ll lose out of a large chunk of money. (And without it, these games likely would not be made in the first place.) Thus Steam can force these unfair terms on developers.
There was also this portion on discounts that was quite revealing:
They’re admitting to inflating games’ prices, so they can then offer a fake discount that’s closer to the actual price they actually wanted the game to be. And then they complain when Valve doesn’t let them list a game on sale for an extended period of time, just so they can essentially scam people. (Probably, once again, standard in the industry and elsewhere, but I feel like that’s gotta be banned by EU pro-consumer laws.)