Thanks to everyone who responded to the poll.It seems like there's a common expectation that enabling "indexable" makes your content available for indexing without additional opt-in to a specific server. This is how Mastodon and other Fediverse servers treat the flag; if you've got the indexable flag set, your public content is indexed for full-text search. (Even if the indexable flag is not set, if you use a hashtag in your post, it's indexed for hashtag search.)