Well you can take the knowledge that Lemmy.world grew 60% following it, look at current numbers for the server, and know at least around 60% of that number has shifted some of their media habits away from Reddit.
But the full picture is unknowable outside Reddit corporate.
Probably more than spez was anticipating though...
But probably not enough to make a bit immediate impact on Reddit. I’m more interested in long term impact, seeing if the people who left were big contributors, or just mostly lurkers
Don't underestimate lurkers. They play a big role by upvoting, downvoting and reporting inappropriate content. They are the invisible force that keeps a website healthy and sane.
Not only Lemmy but other instances and other sites as well. I know squabbles grew by quite a bit, beehaw grew, and so did Tildes. But unless we were able to gather information from everywhere, it's impossible to know. What is heartening is that we do know that it was not an insignificant amount.