This is a bunch of opinion though. I'm not saying I disagree, but I do think it's bad faith to state as fact what is opinion. Is Play a "walled garden" or is it not curated? It can't be both depending on what suits the argument. You may disagree with the policies, but suggesting there are no policies in favour user privacy is just false. You may think they aren't enforced sufficiently, but again this is opinion. The policies are there.
F-Droid has the benefit that it essentially doesn't have to deal with malicious actors. It's very easy to have a high quality library when there are no malicious actors.