> The reason is pretty obvious

I would argue the simple reason is that Amazon wanted to fsck Anthropic to set them back, despite whatever partnership they may claim. The competition at that level is intense and these guys do not play by the same rules that regular people do. They can't flat out murder each other (yet) so they find other ways to do it.

Why? Amazon makes tons of money serving Anthropic models through Bedrock and they seem to have basically given up on their own frontier models.