Your car is working perfectly fine so why should you pay for maintenance?
In an organization of any appreciable size, things change all the time.. and I'm not just talking about code (for which you could have a code freeze in an emergency situation like this), but the external systems you're connected to could change for reasons completely out of your control. Content changes can break stuff because of bugs in your code. Legacy systems could require all sorts of ongoing tweaking and maintenance. And, yes, heat can break your software if the server it's running on overheats.
Twitter is not a palm_os app.
Then in theory.. if you own the hardware and you've locked down the libraries... That code could keep running for a long time. Agreed it's not a Palm app, but with everything locked down, I'd argue it's safe
But now I can third party stuff changing. Payment processors and such. Those don't happen fast though, and 100% not so fast that a company the size of twitter can't work out a sunsetting.
To the heat can break software if the server it's running on overheats. I have a feeling twitter's has a system in place to scale out the faulty server.
My point was, comparing code to a car is silly. A car needs maintenance. Code in code freeze does not.
Your PalmOS app doesn't run on any modern hardware except under emulation. (Which is sad, I loved my Centro and held onto it for as long as I could.) The last release of PalmOS was in 2007, 15 years ago. Most hardware from that long ago is dead, and thus your software is dead. broken down by entropy to the hardware.
If however I have an app and I don't look under the hood for 5 years, it could still run as good as it did when I locked it down. As you said some companies run on apps written for windows98. Those apps are still working as they always did.
I don't think it needs are constantly changing. Like it could freeze for weeks/months. Leave existing bugs and put versions in lock.
I do agree that it will eventually need to change, but that's where selective hiring comes in. Oh system X isn't great. Lets find a team for that, all else remains black-boxed.
How many SSL certificates (internal or external) need re-issuing per month? Some of that can be automated, but in an organization as large as complex as Twitter some will be bespoke and manual, and a code freeze won't stop the clock.
How many new CVEs per month apply to Twitter's services and tooling? How many race conditions or other bugs are lurking, just waiting for the right time or traffic pattern to emerge? Twitter can't freeze inbound traffic without dire consequences.
Twitter is like your car, except that it's always running.
