The point is Meta till now always also released base models.
That would require them to release only fine-tuned model like llama2-chat was. Then they can bork it which would be irreversible. But if they give out base model without some stuff - it can be easily added.
They can ingrain those refusals pretty deep to where it will be irritating to use and hard to fine tune out. Vicuna has a bit of this.
The point is Meta till now always also released base models.
That would require them to release only fine-tuned model like llama2-chat was. Then they can bork it which would be irreversible. But if they give out base model without some stuff - it can be easily added.