In the first half of the 2010s, Friendica appeared to have the solution for this problem.
People needed a Twitter account to keep up with what’s going on on Twitter. They needed a Facebook account to keep up with what’s going on on Facebook. They needed a Tumblr account to keep up with what’s going on on Tumblr.
And they had to log into these three websites separately.
In came Friendica with the goal to connect to anything that moved and then some.
You could run your Twitter account, your Facebook account and your Tumblr account through Friendica.
Perk #1: Three commercial, corporate, popular services, three accounts on commercial, corporate, popular services, but all on one website. With one login. All at once. Plus a better-than-Facebook Facebook alternative that was fully capable of long-form blogging on top.
Oh, and if you were interested in that diaspora* thing, Friendica had you covered there as well.
Even if you wanted to get into contact with folks on (pre-pump.io conversion) Identi.ca or elsewhere on StatusNet, again, Friendica had you covered.
Perk #2: You could use Facebook without actually using Facebook. You could interact with your Facebook friends, but you didn’t have to log onto facebook.com and let Zuck spy on you through that website in order to do that.
Perk #3: You could crosspost to everywhere all at once. You could send literally the same post to Twitter and Facebook and Tumblr. And diaspora*. And Identi.ca/StatusNet. Oh, and, of course, Friendica itself. And LiveJournal and a WordPress blog and Dreamwidth and Libertree.
Not by copy-pasting and sending the same text ten times. But by actually only sending that one message.
And you only had one comment tree under that message with comments from everywhere. Of course, Twitter users couldn’t see comments from Facebook etc. But you, you could see them all in one place.
However, and I know this from personal experience, this didn’t work. Either it was too technical, or people didn’t needed alternatives to stuff that just worked for them, or both.
Also, after a couple of years, Facebook no longer let third parties extract data. If you, as a Friendica admin, were caught doing just that with the old Facebook connector, then Facebook terminated not only the dev license you needed to run the Facebook connector on Friendica, but your entire Facebook account. (For a time reference, all this was before Mastodon was launched.)
This only works for users in North America, though. Even though Meta had introduced this feature for EU appeasement purposes. (“See? We do support open standards!”)
If it still works in the first place, that is. And I’m not talking about loads of Fediverse servers blocking Threads and two Fediverse server applications even having the means to block Threads by user agent rather than URLs.