Only defense is to defederate meta and any instance that chooses to federate with meta

I agree, the decentralized aspect is a huge plus and makes this system . But I think the OP's approach is fundamentally misguided and I have my suspicions for a few reasons.

1. It's a 45 minute meeting that provides an insight into Meta's operations. There's no need to contribute anything, just sit back and listen.

2. There's no reason to post about this and brag about it now. Compare this with what Christian did when Reddit tried to claim Apollo was blackmailing them. There's no leverage now, just some internet points.

3. We have one email and a response. Was there any further communication? How do we know this is all that was said? I could go further and question the legitimacy of this screencap but I'm willing to give OP the benefit of the doubt here.

4. As others have pointed out, how does shutting them out completely stay in keeping with fediverse principles? This is legitimate question since, to me, it seems like despite the risks, it's antithetical to the spirit of the fediverse until they demonstrate bad behavior here.

5. To quote OP's email, "Zero interest in having a conversation with #Meta 'off the record or otherwise." "Otherwise" here is...on the record. So OP also won't meet with them in a completely open meeting?

Look, I get it, I dislike Meta too. But this just seems like a misstep and bragging for zero actual gain.

What defenses are in place?

Think we are in good hand if this is by any indication. Lol