Nowadays AA [1] is IMO a better choice for users, but aside from that I cannot imagine these changes making much of a difference. There's plenty of ebook sources (Kobo, public libraries, etc) whose DRM are trivial to break (meaning Adobe and, as of a few weeks ago, LPCM). For what little content is exclusive to Kindle, it will just end up like WEB-DL content from streaming services: a handful of knowledgeable uploader with a KU subscription ripping content en masse—and good luck stopping them.
1: https://en.wikipedia.org/wiki/Anna%27s_Archive