The only thing this ruling really says is “AIs are not legal persons and copyright can only be held by legal persons.” Which is not particularly unexpected or useful when deciding other issues being raised by copyrighting AI outputs.

These models are just a collection of observations in relation to each other. We need to be careful not weaken fair use and hand corporations a monopoly of a public technology by making it prohibitively expensive to for regular people to keep developing our own models. Mega corporations already have their own datasets, and the money to buy more. They can also make users sign predatory ToS allowing them exclusive access to user data, effectively selling our own data back to us. Regular people, who could have had access to a corporate-independent tool for creativity, education, entertainment, and social mobility, would instead be left worse off with fewer rights than where they started.