Maybe nobody reads it when they have automatic updates enabled, but I read the changelogs for every app that has them on F-Droid, even though their update flow is not optimized for this. For projects without changelogs, I'll sometimes check the commit messages.

Quality of changelogs has a big impact on how trustworthy I perceive a project to be. Releasing new versions without a (meaningful) changelog says that you expect blind trust from your users; that you expect them to update anyway regardless of the changelog content; or that you don't consider them able to evaluate whether updating is in their best interest -- in summary, "we know what's best for our users better than they do." Whether or not that's true, the attitude strikes me as vaguely paternalistic. It feels to me that a developer who thinks so little of their users would be more inclined to try and pull a fast one.

As an example, Signal has recently stopped writing changelogs for many of their beta releases, and it has affected my trust in them, and willingness to install said updates.

Let me be very clear: I am NOT saying lack of changelogs makes a developer less trustworthy. I AM talking about how they make me feel about them. I'm also well aware that this is an indirect measurement, so there's some variability and Goodhart's law applies (https://en.wikipedia.org/wiki/Goodhart%27s_law).