Evil people can do things that look good on the surface. He probably has no skin in this game just collecting free karma points.

I can guarantee that he has almost zero interest in “karma points”. I worked for FB years ago and that is not how he sees the world or sets direction did the company.

Almost certainly this is part of some grandiose bet which could have a chance to pay off massively in the future (AGI or similar), or a way to prevent an expensive dependency.

Facebook hasn't had much success getting people to use their hosted AI, so they're making those models free instead, to kneecap other companies who are trying to get paying customers for their own hosted AI. This gets people to ask themselves things like: how many months of Claude Max it would take to pay for hardware to run Muse Glimmer (the Meta model in question) offline?

As they say, even Hitler built the autobahn.