Title, basically. Back on Reddit, there was a way to add a user as a friend. It made it easer to identify people (Apollo would highlight friends differently), as well as to see what they’re up to across all communities. There was even a feed for all posts by all friends, which was really useful.
Some social media focus on people, some on subjects.
One type tends to create “influencers” and circle jerking opinion bubbles, the other forces you to interact with different opinions around subjects you like.
I hope Lemmy stays on the second type.
Besides, with the volatility of instances, and user logins not being universal across instances, Lemmy also makes it harder to do that, and as a bonus devalues karma hoarding.