If you host your email server would you wonder if you should block emails from GMail addresses?
Why? If Meta or Google want data from the Fediverse it would be very easy for them to get it.
If you block some users from interacting with other users you are fragmenting the Fediverse, making the experience worse and people will avoid federation in general because it won't guarantee they can interact with who they want.
And you won't make any damage to Meta or Google. Actually, they are not joining the Fediverse because *that* would damage them and being good for the people.
They can access the data from the Fediverse (and maybe they are) without running a public instance or involving their own well-known domains, you know it right? It is even easier for them than indexing the Web and parsing HTML pages, because the Fediverse content is already structured and available through API.
I am not convinced that it would help Meta or Google, rather help people move to the Fediverse while still being in contact with people that are still on Meta and Google. The same convenience of moving away from GMail to another email provider.
Again, if they are not joining the Fediverse it is because the ones that would take advantage of it are us.
I dont consider them joining as a reverse Trojan horse working in our advantage but time will tell.
Happy to turn out being wrong on this.
Is there allready a please-remind-this-toot-in-a-year bot? 😁