Metrics! By which I mean scientifically-privacy-guaranteed ways to help us understand how our platforms and technologies are used, released as open data sets. Let's stop pretending we know how people use GNOME or KDE or this app or that feature—let's find out, ethically.
The FOSS world used to be at the forefront of globally-distributed online-first tech (version control! realtime chat!). There's no reason we should tie our hands behind our back when it comes to making our software better.