Not legally. Liability is a big thing.

The thing is, you don’t need to actually block usage to make something illegal. You make it so toxic that company wants to be seen publicly using open models

Companies would secretly use self-hosted models internally because it would give them a enormous cost advantage.

Sure, companies can indeed do illegal things

But how would the actual weights it be made illegal without violating the 1st amendment?

By ignoring the 1st amendment? The US has a tendency of ignoring its constitution whenever it's convenient.

Don't be glib, the 1st amendment is taken VERY seriously.

Im not sure if you’re joking or not.

- the US strictly regulate cryptography https://en.wikipedia.org/wiki/Export_of_cryptography_from_th...

- some prime numbers are considered illegal https://en.wikipedia.org/wiki/Illegal_number#Illegal_primes

I don’t think banning open weight is that far fetch compared to those

Neither of those worked very well.

Ok, but that’s a different thing altogether. I personally expect a ban, that doesn’t mean it will be very effective, but that does mean it will have a meaningful impact (such as not being able to offer open weight models as a service)