That's true but it depends on what we mean by "cloud storage".
There aren't lots of definitions for the term. It simply means to allow storage of information. Besides OP_RETURN there are standard scripts, which you can't distinguish if they're used as cloud storage or for legitimate usage.
If it is the very small size we allow to be stored in an OP_RETURN output for example
Comparably to what standardness allows, it's not. You can fit as much as an entire, 4 MB block in an OP_RETURN output, and it will be valid.
But if it is the exploitation of protocol to store any size without limit (except the block size) then we can prevent it well.
Which part of the protocol Ordinals exploit that allow storage of any size without limit?
It won't break anything and saying that a single transaction with 1 input/output must not be allowed to be ~4 MB in size to store garbage on chain to scam idiots who would pay for this garbage, is not called "subjective criteria".
Oh yeah, it very much is. What's the problem with the transaction size? Why can't it be 4 MB? Or 1 MB? And there you go, a very big, future CoinJoin was just made invalid. What people do with their money isn't your business. If you think it's garbage, and all that are just greater fool theory schemes, then the best approach is to let it pass, as you're so sure it will!