I disagree strongly with your framing.
Protocols are not just technical specs. They are also governance agreements.
There is a difference in kind between AT Protocol, developed and implemented by one VC-funded startup, and ActivityPub, an open standard with patent protection, implemented by >100 projects.
On the Internet, we collaborate on standards and compete on products. Experiments happen within that open compatibility structure.
UPDATE: edited for tone. Apologies to Mike.