Here’s some stuff that I’d meme about:

• Mastodon users thinking the Fediverse is only Mastodon
• Lemmy users thinking the Threadiverse is only Lemmy
• Mastodon users thinking the Fediverse started with Mastodon
• Mastodon being ridiculously underpowered in comparison to just about everything else, particularly Hubzilla and (streams)
• Mastodon users wishing Mastodon (or, better yet, “the Fediverse”) had certain features which are readily available just about everywhere outside of Mastodon
• Mobile apps built against only Mastodon
• Fediverse tools built against only Mastodon
• Pleroma being lightweight
• Mastodon’s culture which Mastodon users are trying to force upon the rest of the Fediverse
• Forkey antics such as "Speak as cat"
• Forkeys in general
• Forkeys inspired by Blåhaj vs Mastodon’s mastodon plushie
• Mastodon users still uploading videos to YouTube and not to PeerTube
• Hubzilla’s UI
• Sharkey’s infamously bad Mastodon API implementation
• Friendica federating with everything, especially juxtaposed with some Mastodon users not wanting to federate with anything that isn’t vanilla Mastodon
• Hubzilla’s ability to host Web pages
• Nomadic identity
• Bluesky’s AT protocol seeming like a cheap knock-off of the Zot and Nomad protocols in parts
• Self-proclaimed Fediverse experts who actually barely know anything about Mastodon and don’t know anything about the rest of the Fediverse
• Character limits
• Threads perhaps wanting to EEE the Fediverse vs Mastodon actively trying to EEE the Fediverse right now
• Mastodon’s poster-side content warnings set in stone in what they want to be the Fediverse culture vs Friendica’s, Hubzilla’s, (streams)’ and Forte’s automated, reader-side content warnings which have been around for longer
• Generally, the Fediverse being older than Mastodon
• Lemmy only barely federating with everything else
• /kbin essentially being dead
• Permissions on Hubzilla and (streams)
• “Conversations” on Mastodon vs conversations on Friendica, Hubzilla and (streams)
• Certain points in the Fediverse history

Granted, I guess almost all of this will fly even over most c/Fediverse users’ heads due to how detached Lemmy is from the rest of the Fediverse. But I don’t really expect that many more Mastodon users to understand it, and those who do may be offended. Oh well.