While you have some valid points, I do disagree with you on some levels. Sure, for the average intermediate user, a one time fee to switch to Davinci or Hitfilm is worth it. However, for the more advanced editor, compositor, and VFX artist, After Effects has no equal. I don't really use premiere much, but if your points about the software being the same each update for Pr, they don't hold up with Ae. In fact, the most recent update brought content aware fill for video which is unprecedented and a huge step into the future of editing. Ae also has a great community of plugin creators which really enhance the user experience and capabilities, especially with the recent things Red Giant and Videocopilot have been putting out. It also has great integration with softwares such as C4D, which is just great.
TL/DR: While premiere may not be worth, After Effects is great for the advanced user.
Also, for the people that just use Photoshop for basic touchups and are looking for a good software with a one and done price, look in to Affinity Photo.