I’d use a weather app 🤙 lol

This'll probably sound like a broken record, but I'd say it depends.

The downside of redundancy is that it could clutter and overwhelm a user on a home screen or settings screen for example.

One kind of flow you might consider is something like deep-linking. A conditional banner notification saying there's now a dark mode could link to the toggle on the settings page instead of there being a toggle on the home screen header and one on the settings page.

The deeper it’s hidden the less use it will get

Different for different apps.

For podcast apps, I want multiple ways to add an episode to my queue.

I don't want to have to always go through a series of clicks to navigate to a certain screen to perform a routine action.

I think it comes down to frequency of action originating from each page.

Ok, but don't overdo it. I guess depends on what it is. On snort for example, you can follow people by clicking on their profile or by hovering over their PFP right from the feed. Both ways work and there are benefits to both. Same goes for search, no need to click a profile to follow a person from search.