Being the official Harry Potter director must be a pretty cushy position, so I'd think he must be pretty happy with things. All the credit (or blame) goes to JK Rowling no matter what, so Yates can just cruise under the radar and enjoy the guaranteed success each film will have.
Yeah Star Wars made a big mistake thinking that they could have big directors on all these films. It would be one thing if they were genuinely going to let these directors have their creative freedom, but as soon as it became clear that that wasn't going to be the case they should have quit while they were ahead.
These franchises really do work like TV now, the showrunner is whoever is in charge of the franchise and the directors have to answer to them. So no surprise that TV people like The Russo Brothers and Joss Whedon thrive under those conditions.