[barelyusable]

The issue you describe isn't technical. It's mostly social. Your colleagues don't question the sense of updating the frameworks for no reason.

It's not that CSS/HTML will stop rendering. So you can just stay with 5 year old framework if you want. e.g.: old Twitter Bootstraps and old Angulars will still work, so if you've written code in that, don't touch it. But people get excited about updating, because they like to get features they won't be using.

The long-lived software is hard, and make sure you don't leverage yourself on the other end. Writing stuff to survive many years can be stressful. And you'll see 10-year old hacks and workarounds in the code as well. Just look at some Linux/FreeBSD kernel code. You can also read what Raymond Chen is writing about Windows kernel hacks to make customers happy.

But yeah: embedded, and everything infrastructure related should be long-lived. Even mobile: when writing www.sensorama.org I've mostly used ObjC stuff even though Swift existed for 3+ years now I believe. And all libraries and proprietary apps are and will be ObjC for many, many years. There's just not enough reasons to upgrade.