There is no corollary. You're connecting the wrong parts of the analogies. The Mythopoeic Society is a collection of particular people in a particular context. LJ is a collection of particular people on a particular platform. If my LJ friends move to a less desirable platform, I'm torn; I like the people, but I don't like where they've gone. If Mythies drop the Society in favor of ... well, actually, in the late 70s a lot of the early Mythies did drop the Society in favor of Star Trek and Star Wars fandom, shows I don't consider 1% as good or enjoyable as Tolkien and Lewis (though a lot of energy was spent trying to prove that they were, just as some praise the FB platform now), I wasn't going to follow them there either. Because it's not just the people, it's the context as well. I love my Christian friends, but I'm not going to join their churches either.
I can't do anything about the fact that you've mischaracterized some features of LJ ("my friends' list on LJ takes me off the main page to read the whole post" - that's only true if they use a cut tag, which on my FL is rare, and if the post is long and cut, you don't have to follow it and read it if you don't have the time, same as you don't have to read an FB Note; and if you don't like moving off the main LJ FL page, you can open a new tab; I do that all the time, and I really see no fundamental difference between that and the balloon expansion that FB uses - see, I really do know something about how the FB platform works - same thing is true for making a comment; and, if you dislike LJ's advertisements but like the glitter on other websites, you can customize Adblock; in fact, that's how Adblock works: you point to something specific and say "I don't want to see any of those any more").
But regardless of whether the contrast between the platforms is fair, that may be the reason why you prefer the FB platform, but it's not the reason that "Fb does a better job *for me* of keeping me in loose contact with a lot of different people." FB does that for the reason I said: because the people are there. If you had few friends on FB, it couldn't keep you in contact with them. If they were on LJ, LJ would keep you in contact with them, and all the long posts and cut tags in the world wouldn't prevent that. In fact it didn't.
no subject
I can't do anything about the fact that you've mischaracterized some features of LJ ("my friends' list on LJ takes me off the main page to read the whole post" - that's only true if they use a cut tag, which on my FL is rare, and if the post is long and cut, you don't have to follow it and read it if you don't have the time, same as you don't have to read an FB Note; and if you don't like moving off the main LJ FL page, you can open a new tab; I do that all the time, and I really see no fundamental difference between that and the balloon expansion that FB uses - see, I really do know something about how the FB platform works - same thing is true for making a comment; and, if you dislike LJ's advertisements but like the glitter on other websites, you can customize Adblock; in fact, that's how Adblock works: you point to something specific and say "I don't want to see any of those any more").
But regardless of whether the contrast between the platforms is fair, that may be the reason why you prefer the FB platform, but it's not the reason that "Fb does a better job *for me* of keeping me in loose contact with a lot of different people." FB does that for the reason I said: because the people are there. If you had few friends on FB, it couldn't keep you in contact with them. If they were on LJ, LJ would keep you in contact with them, and all the long posts and cut tags in the world wouldn't prevent that. In fact it didn't.