2014's flagship Lumia 930 is no longer eligible for new versions of Windows 10
Technology moving on is one thing.
Stable technology needing no updates is another.
Forced obsolescence due to lack of updates is another entirely. I spend that much on a bit of kit, and look after it, I expect to be able to continue using it.
I upgraded my mobile at the end of last year, having destroyed the screen in a rather unfortunate drop, and the upgrade worked out cheaper than my previous contract, but not as cheap as the sim-only deal I was going to go for - using the same hardware because it was, prior to it's percussive demise, still working perfectly.
Companies should support devices for their expected lifetime. With current technology, that should be at least 5 years. - They should expect to do this, and imho should be held to do this - especially with security issues being a worry - just how many unpatched phones are out there right now?
I don't have a Windows Phone, but I experienced exactly the same with my first, and last ever iDevice. This abandonment is one of the reasons that I'm not going to buy another one.