All of these things used to annoy me as well. Then I downloaded the app and subscribed monthly to get rid of the ads. Now my reddit experience is awesome.

Reddit isn't a public service. It's a private company trying to increase their profits. The native app experience is way better than the website. Undoubtedly they see higher engagement from folks using the app, so want as many people as possible to use it.

Ads looking like posts? Sounds like they are trying to monetize their traffic. If you don't want to see the ads, pay for the service.