[omnimus]

The federation mechanism that will win will be the one that forgejo/gitea supports first.

Everybody is moving either to codeberg or more likely forgejo instance.

[preya2k]

Forgejo already supports ActivityPub, albeit only for a minor use case (starring repos), so according to your definition, it's decided already.

[omnimus]

I don't think thats so clear. The forges could support multiple federation systems and if for example someone made quality PR for the ATproto version that could get meged and adopted.