Thank nice analysis :)
Hence mastodon is the serious place and lemmy is the fun comic place in my life. Piefed would be the serious version of Lemmy I guess? shrug
I don't know. On french that would be the opposite. Mastodon is more chill than the threadiverse. We have lot meme but that depend on your subcriptions and the french fediverse mostly use mastodon.
I don't see piefed as a serious version of lemmy. i can subcribe to meme community and block every post on politic by keywords or community. On mastodon, i don't know what will they post because they don't have group, community.
For me the huge difference, until lemmy v1, is that piefed merge comment from post that share the same link, and merge every related community under a feed. For example this one : https://piefed.social/f/fediverse
And there are some front-end as Blorp, voyager (?). Pylova is also worth mentioning, they focus on UI and improve piefed features. It pain me to see them apart...