>>24539345They are removing the feature to transfer ebooks you've purchased to your PC (You can still read those books via the Kindle app or Kindle reader online). Basically like how you can buy a show on Prime Video, but you can't download it and share it and shit. It's locked to your account. And if Amazon, or whoever should remove it, you may not own it anymore (not sure this is relevant to the ebook side of things though, how often do books really get banned?)
It's the whole "you don't actually own your digital goods" issue. For the VAST majority of readers, especially on a website like this, t's a non-issue, just people moral fagging. You can still download any and all books from anywhere and load them on your Kindle. This will never change, don't worry.
As for ads, there's literally just an ad for a random Kindle book on the lock screen. For $20 more, you can buy the ad-free version. It does not affect use at all whatsoever.