One advantage to using sequences (not serial, but close) is that you can drive all IDs from one sequence, helping to prevent mistakes of ID misuse.
No and this is all well known stuff, none of it seems like a good reason to stop using
Yeah, that's why the post is an opinion piece. I got bitten by the permissions issue and wanted to write this for my peers at work. As long as you're aware of tradeoffs, it is fine to use it.
Personally, I have grown to like the identity columns since I work across different database vendors.
It would be nice to have a link to the PG docs for identity columns in addition to the Wikipedia article about them.