What's the converse: the behaviour needed, from the point of view of the group, trying to lower the costs of joining?

One of the dark arts that I've practiced ocassionally in committee meetings was to get all the "font changers" to put forwards their suggestions, listen carefully, praise and accept the ideas, and leave the meeting with all my plans accepted but in a different font and grammar.

For a rationalist group, this isn't ideal, and you don't want to go around accepting millions of random suggestions. But you could write back to the font changers saying: if you are willing to join the group, I will change the font (or at least have a continued discussion with you about which font is ideal). Maybe another norm should be:

If the efforts involved in addressing the issue (either through changing it or discussing it) are less than the benefit of bringing the person on board, and the suggestions are not made in bad faith, then you should bring them on board.

Of course, there's no reason that Eliezer specifically needs to address the issue personally - some delegation would be fine.