I've had a merge request open to add an app to F-Droid for 4 months now.
It's gotten some attention, and I've addressed all the requests for changes I've gotten. But still, no resolution after 4 months.
In contrast it took me a few days at most to publish to Google Play and the App Store, which I did at the same time as I submitted to F-Droid. And I've shipped numerous updates to both since then.
So "Switch to F-Droid!" rings a little hollow for me.