There are no known plans for Google shutting down Blogger.
https://www.cnet.com/tech/services-and-software/your-old-goo...
I wonder if they made a big list of the old content that would get deleted under their policy, and decided that some of that actually still brings in enough ad revenue to be worth keeping. And it was easier to just keep everything than make carve-outs to the deletion policy?
Medium it's so bloated and clickbaity, that I would take an old regular blog in WordPress or blogspot despite being more ugly. A lot of technical documentation of some niches, is still only present in blogs of this kind.
(Full disclosure, I'm a paying user of mataroa, but no other relationship to either of those sites.)