I'm worried about the issues in the article (They are likely an inevitable consequence of the funding model). For now, I'm loving it! I didn't have Twitter or X. I'm using it to follow various science and engineering feeds. It's fantastic, and the people are friendly; some of the highest quality discussion (but short) I've found online. (Not to HN's level though! )
To make Discover useful, I recommend aggressively muting or blocking bottomfeeder political content. If someone is only posting tribal or identity politics, block. I bring this up, as I think it would resolve a subset of the complaints I've seen in this thread and elsewhere.
I wish you could have all your feeds combined, but this appears not to be possible.