Nothing against OP, but man, this is a rough one. This is nothing more than an opinion piece with bad takes.

What a bullshit article. I've highlighted some of it below:

Forums became uninteresting because I was looking for more structured forms of online publishing

Forums are pretty structured. Twitter and the new reddit are way less structured unless you're talking about structured with ads built in. That aside, that's a personal preference not a fact of the internet.

it’s just as uncool as Twitter’s Elon suddenly asking precious dollhairs for API access

if you use "dollhairs" in an actual publication you're going to find it hard to be taken seriously.

As a product owner, all you have to do is try them all, and make a list of all their features to know what Reddit misses. And can you really blame them doing just that, especially in a pre-IPO state? After all, investors will invest in Reddit, not 3rd-party apps piggybacking on its APIs.

They should have built out the feature set and had a good usable app before making the decision then. It was a dumb decision, full stop. Re-reading this it makes even less sense. Who is blaming them for researching 3rd party apps? And, OF COURSE, the investors are investing in reddit. That's why they should have a usable app of their OWN before dropping the ball like this.

While admittedly, good design alone doesn’t improve much the valuation of a product, good design can distract from bigger issues and helps prevent users from flocking to 3rd-party offerings

Good design absolutely adds to the valuation. Like, what? If an app performs as badly as the native app to the point people have no choice but to use 3rd party apps for basic things like, I don't know, MODERATION, you need a drastic overhaul before shutting out those 3rd party apps.

For starters, subreddits going dark — aka making everyone else’s content go private without their consent — could be considered content theft. Imagine, for instance, a Medium publication unpublishing all your articles because their owners suddenly disagree with Tony Stubblebine. I’m pretty sure it wouldn’t land well. The same applies here. Many Reddit users find themselves having to side with either Reddit or some small 3rd-party app developer. Pragmatically speaking, a large majority of them will side with the platform owners because ultimately those apps are nothing without Reddit and its API. Going back to Medium as an example, when the Medium Partner Program was introduced, some big publications reacted very similarly, got angry, grabbed their toys and left trying to take with them all their writers. Except it didn’t work, because people ultimately wanted the platform and its reach, which was already proven, as is Reddit’s.

I stopped reading it here. They lost me at this point. The author of this is either playing to reddit's side, has no idea of what's driving the current situation, or a mix of the two. There's no way someone that actually wrote an article about this, and actually researched it, would come away with this take. Comparing a paid service, like Medium, deleting the articles and things you have paid to access is vastly different than shutting down an established forum(subreddit), that voted do so, that was free of charge the entire time. I know they have paid subscriptions and their dumb NFT stuff, gotta pay the bills somehow, but that was such a brain dead take I had to stop.

I haven't read many Medium articles but if they're all this low of effort I don't feel I've missed out on much.

edit:

Many Reddit users find themselves having to side with either Reddit or some small 3rd-party app developer. Pragmatically speaking, a large majority of them will side with the platform owners because ultimately those apps are nothing without Reddit and its API.

This part is the part that made me truly stop reading. I could imagine spez writing this himself.