The spam problem was exaggerated and used as an excuse to avoid FTC scrutiny. Even if 99.9% of federated inbound messages were spam, that doesn't mean it all re

The spam problem was exaggerated and used as an excuse to avoid FTC scrutiny. Even if 99.9% of federated inbound messages were spam, that doesn't mean it all reached the client. Most e-mail is spam but very little makes it to the user. (AFAIU, the primary motivations were 1) lack of MSN reciprocity, and 2) Google's endless dithering and floundering attempts to capture users the same way Facebook, WhatsApp, etc had and/or were going to.) Large walled garden IM platforms have the spam problem potential. It's solved by using whitelists (via invites) instead of blacklists. The same mechanism is trivial to accomplish using XMPP, and I'm sure there are already XEPs for that. (Multiple, even!) You can end up with invite spam, but that's exactly the problem you see on Facebook, WhatsApp, etc. As for me, I ran my own XMPP server for years along side an SMTP server and never received XMPP spam. Both my XMPP and e-mail addresses were the same, and my e-mail address had been in use since circa 2000 and exists on countless spam lists. I doubt the spam problem could have been very significant. I never used a GMail or GTalk address, but of the people I know who did, some of whom I chatted with over federation, I never once heard of GTalk spam. Anybody who cares about privacy should care about federation and should advocate for federation. Being cynical about the potential is counterproductive. If you think federation is impractical because centralization is required to prevent abuse, then you must admit that privacy beyond the current status quo is also impractical; just give up. If you don't want to give up on privacy, don't give up on federation. The technical problems to federation will never go away, but the will to solve them is entirely voluntary. (Though, if we legally mandate federation then that's at least a substantial, long-term commitment.)