This question is especially for people who have joined in the last week. Have you used other fediverse platforms or is this your first time really using one? What do you think of it so far? Are you aware that you can comment on Lemmy posts with a Mastodon account?
Is Matrix considered part of the Fediverse? If so, Matrix would have been my introduction to the Fediverse.
I believe it isn’t strictly considered that, because it doesn’t use ActivityPub (to my knowledge) as it is a protocol in-of-itself.
It’s a different thing. E-mail, Matrix, and ActivityPub are all different protocols. Mastodon and Lemmy both exist on the ActivityPub (i.e., the Fediverse).