I noticed that some of the mods here are also the mods of r/experienceddevs. That subreddit is quite active. Perhaps it would be effective to have automoderator throw a sticky on every post there, just saying welcome to r/ExperiencedDevs, please follow the rules, etc and at the bottom: Did you know we have a Lemmy community? With a link here.
The conversations here might be different and deeper, with the many Linux fans here.
Of course. People that left and came here because of the API stuff are (IMO) inherently smarter people with a predisposition toward FOSS technologies.