You can always dump your licenses from the web interface, pull down the books with the Adobe fulfillment software and then strip the DRM using calibre.
The problem with that reasoning is, it's not like Google is rolling a percentile die. They shut down projects that don't pay stockholder dividends, no matter how popular or widely used those projects are. So...
"shut down" seems a little strong since it was replaced with Youtube Music. For most users it was a UI change but otherwise they didn't even notice. This is very different from other products that were actually shut down where they just turned them off.