From what I understand due to the way that Lemmy handles federation, it doesn’t (currently?) have a way to handle an instance changing its domain name and still being able to communicate or even an individual user changing their instance and retaining their comments/votes/etc… (this might be more ActivityPub limited since the way Mastodon does it still seems pretty hacky and just a work around for underlying issues).
From a website perspective, yeah, just change some settings and you’re good to go and accessible on the web, but that doesn’t mean that anything regarding Lemmy is going to actually work.
When I installed fdroid from their website a month or two back it was like 2 or 3 clicks. Then whenever I want to install anything from there it’s an extra click or two over what it would be from Play.
I’ve seen people click through way more complicated processes than this without even knowing they did it. Modern computing has taught people to just keep hitting whatever the approval text is (yes windows, I really do want to copy all of these god damn files. Yes, really, I still do! Yep, again, ALL of them!)