I doubt it was a cost-driven decision on the basis of running the servers. My guess would be that it was a security and maintenance burden that nobody wanted.
They also might have wanted to use the domain for something else.
The nature of something like this is that the cost to run it naturally goes down over time. Old links get clicked less so the hardware costs would be basically nothing.
As for the actual software security, it's a URL shortener. They could rewrite the entire thing in almost no time with just a single dev. Especially since it's strictly hosting static links at this point.
It probably took them more time and money to find inactive links than it'd take to keep the entire thing running for a couple of years.
My understanding from conversations I've seen about Google Reader is that the problem with Google is that every few years they have a new wave of infrastructure, which necessitates upgrading a bunch of things about all of their products.
I guess that might be things like some new version of BigTable or whatever coming along, so you need to migrate everything from the previous versions.
If a product has an active team maintaining it they can handle the upgrade. If a product has no team assigned there's nobody to do that work.
Best analogy I can think of is log-rolling (as in the lumberjack competition).
Arrival of new does not neccessitate migration.
Only departure of old does.
This seems like a good eval case for autonomous coding agents.
You know how Google deprecating stuff externally is a (deserved) meme? Things get deprecated internally even more frequently and someone has to migrate to the new thing. It's a huge pain in the ass to keep up with for teams that are fully funded. If something doesn't have a team dedicated to it eventually someone will decide it's no longer worth that burden and shut it down instead.
How? Barring a database leak I don't see a way for someone to simply scan all the links. Putting something like Cloudflare in front of the shortener with a rate limit would prevent brute force scanning. I assume google semi-competently made the shortener (using a random number generator) which would make it pretty hard to find links in the first place.
Removing inactive links also doesn't solve this problem. You can still have active links to secret docs.
Cloudflare offered to run it and Google turned them down:
Yeah I can't imagine it being a huge cost saver? But guessing that the people who developed it long moved on, and it stopped being a cool project. And depending on the culture inside Google it just doesn't pay career-wise to maintain someone else's project.
It's a strange thing to consider 'since 2018' "a long time". Only in tech circles is this so, not in normal life.
Edit: nevermind, I had no idea Dynamic Links is deprecated and will be shutting down.
Here is a service that basically makes Google $0 and confuses a non-zero amount of non-technical users when it sends them to a scam website.
Also, in the age of OCR on every device they make basically no sense. You can take a picture of a long URL on a piece of paper then just copy and paste the text instantly. The URL shortener no longer serves a discernible purpose.
