I'm trying to understand the way Mastodon works. Back in the day I started with IRC and then the many php-based forums and then reddit which led to lemmy. I never used twitter or similar platforms.
My understanding (and this is where I need help) is that all of the above are topic-based, whereas Mastodon is person-based? What I mean is that on lemmy I subscribe to things based on topic and I don't really care about usernames or user profiles, I only care about discussing a topic. It seems to me like Mastodon is the opposite? You follow persons and what they might say about any topic?
Is there something I'm missing here? Are hashtags close enough to sorting it by topic that it works just like a topic based platform? Is this difference inherent or just in my head because I don't understand Mastodon?
Mastodon is microblogging. As others have said, it's similar to Twitter. Lemmy is a link aggregator with a comments/conversation section per link, like Slashdot, Digg or Reddit.
I think the thing that people forget to do with Mastodon is to follow hashtags. The feature wasn't there early on but it's been there for probably a year or more now. Then you block or mute the accounts you don't want to see that post under those tags.
It's a useful substitute for following accounts when you have no idea which accounts to follow. You can then curate and actually follow accounts whose content outside those hashtags also catches your eye.
On the link aggregators there are the groups which don't exist on Mastodon, but that's what hashtags are for, right? Marking the topic.
The only hard part about it for me is feeling bad about blocking innocent accounts.
Also worth mentioning is that Mbin instances exist, and that software is basically both Lemmy and Mastodon rolled into one site. The posts aren't fully integrated though. You have to click something to view the microblog side of things and click something to go back.
I feel like less common or more specific hashtags tend to work better. If you try to follow common words like art or music or dogs, it can overwhelm your feed and a lot of it is mediocre. If you browse those tags, you might see more specific tags used along side them focusing on what you actually want.
I can only speak to the topics I followed on another account, but it provided plenty of reading for those topics. Whether it covered all possible posts and whether it works well for all topics, I couldn't say.
It does kind of rely on people tagging things properly, which people might not do if they're on a Mastodon instance specific to that topic. But then, they ought to know that those posts wouldn't Federate well, and indeed, might not want them to.
Hashtags still only show you posts that are specifically addressed to users on your host site. They just act as a quick-search feature. You need some kind of "actor" to re-address things to people who aren't following the OP in order to get true propagation across the network. This is what guppe groups do, and what Lemmy communities do.