There are a myriad of reasons to be concerned about the military adopting this kind of tech. If it's reasonable to be upset at the military, it seems equally reasonable to be upset at entities that enable the military.
I don't think it's a matter of "should", but rather, if you're upset at one, it doesn't make much sense not to be upset at the other.
Because getting mad at one is more appropriate and getting mad at the other would be pointless. Militaries will adopt this technology, whether Meta or the big names allow it in the TOS or not.
I also don't get angry at gun manufacturers for the ways their guns are used; I do however get mad at legislators and citizens who enable easier access to guns and promote gun culture.
There are a myriad of reasons to be concerned about the military adopting this kind of tech. If it's reasonable to be upset at the military, it seems equally reasonable to be upset at entities that enable the military.
I don't think it's a matter of "should", but rather, if you're upset at one, it doesn't make much sense not to be upset at the other.