One of the remaining 3rd party Reddit apps (Relay) has begun discussing what it would be charging for subscription fees. Imo, they actually seem somewhat reasonable. The weird thing is that every upvote or downvote is an API call so you can rack up a huge number of API calls from voting.
Also, while the costs might be reasonable now, there's nothing preventing Reddit from jacking up prices again.
Edit: Also, there wouldn't be any NSFW content with the app.
NSFW is pretty big, yeah. Mind you, that includes all posts tagged as nsfw, even those with only “disturbing imagery” or tagged as a joke in non-nsfw subs. And even if nsfw is not your thing, it’s simply the bad principle of segregating user experiences and locking content behind what’s effectively a personal data pay wall that stinks to hell.