Each participating distro's maintainers will need to publish a compliant distro flavour in binary form in order to remain on the "good guys" key list. Negotiating and implementing the compliance criteria, as well as maintaining the entire thing will all consume additional man hours, which open source maintainers famously have very little of.
If a distro/appliance maintainer is committed to continue to participate, an incentive emerges to gradually push the compliant version as the default, the later possibly the only supported version of their offering. Unhappy users may of course switch, but the more this proliferates the less good places will remain for them to go to. This pattern of enshittification by infiltration and complacency manipulation is the one we see almost everywhere in the modern tech.
Hopefully a well-enough organised minority of uncompromising users and developers always remains in tech, if not in the Linux world then in the BSDs. We will always need to keep our eyes open for the false values masquerading as tech dilemmas like this one.
I'm not a lawyer so I will not get into the legal ramifications of distributing locked-down binary versions of free software. However, it's clear that without obtaining the private signing key a user will never be able to modify that software on their system for the purpose of running the game, which may or may not infringe on their freedoms as provided by the licenses.