The obvious benefit to going through a publisher is the marketing. They do it all.
Not speaking from experience (but my uncle was a music publisher, so, similar).
If you built a game that would do well on a console then I'd go the publisher route. Though I have no idea how one would do that. My gut feeling is that it would only be possible if you had a network in place where someone you knew could put it before the right people. Which is not most peoples situation.
I.e. you were a game dev for Atari, met people, started your own company, and now know who to call.
From a purely business standpoint, if you could show that your "game" can, with a high degree of accuracy, mine user data, a publisher would consider picking it up simply for the tech.
In this industry, you have to keep an eye on the big picture.
Apps like Tik Tok, Instagram, and most GATCHA games are making money from selling stolen user data (that the user "agreed" to in your terms and conditions.
I have 2 apps published under my own brand "Delta Star Studios," and while neither are monetized ATM (waiting for more installs), they both have detailed plans for monetization down the road.
The job app will use ads
Kaneki Island will have physical toys and a trading card game to geneate revenue via real world merchandise.
Again, have't implemented the ideas yet (outside of prototypes), but I know how I will monetize in the future. Remaining your own publisher allows you to retain all rights.