If you still have a land line you can dial locally without even an area code. This worked in most countries. Some mobile phone networks kept this tradition although in a weirder way: you could dial locally when physically located in those areas, and your phone would display the area code you were in on the its standby screen. Which worked as long as you weren’t on a border between cells and it picked the wrong one.
Over time this went away.
I don’t think this is what you have experienced, but it was a nice thing that blurred the lines between land line and mobile phones for a little while, and I think it’s interesting.
If you are a big company there are often ESCROW agreements for things like this. I have encountered the “data dumps” from time to time and whilst it’s “better” it’s not ideal. Half finished documentarian, virtual machines of mis-configured OS installs… it’s almost as if it was just a straight copy of the development environment as it was just as they made the final version of the software…
But it’s better than nothing.
Main issue I can see with this forcing open source would be libraries and frameworks licensed from others who would likely still be in business and wouldn’t agree to those parts becoming open sourced. See also WinAMP https://www.theregister.com/2024/10/16/opensourcing_of_winamp_goes_badly/