This is true, and an important thing for me. If I browsed specific subs, I’d definitely be able to see the difference. But I used reddit for just browsing the popular/cool topics of the day. I did subscribe to subs but rarely specifically entered one and browsed its content. I basically just blocked subs I didn’t want and did it that way, so Lemmy isn’t that different for me
I think the ONLY useful way to use it is how I do, which is just every couple of years to track how my own views and beliefs have changed throughout me aging (still just for fun/personal interest!). It’s not perfect but it can at least measure the change in a single person. To nobodies surprise I started bottom left, close to centre 10 years ago, and now I’m significantly closer to the bottom left corner