Google shuts down a lot of things, and usually there is nothing to do and parts of the internet break forever. But…I feel like this is one that would be cheap and at least possible to mitigate without Google’s help.
Crawl for all goo.gl links prior to the 2025 shutdown, cache and enter the link and the redirect link into a database, and create a simple open source in-line replacement extension for browsers that intercepts goo.gl links and replaces them with the real link. These are just URLs, so the database even for hundreds of thousands of entries shouldn’t be huge.