mosspa
One of my dear friends once imparted a few words of wisdom about 25 years ago that made me think, quite hard. I'm only paraphrasing, but Nick's post to some USENET forum stated, 'a synth or piece of software will never be worth TO YOU less than it was when you acquired it'. Yes, Windows may change (and likely will), but nothing prevents you from immortalizing the version you already have. If the current version of SONAR works for you, all you need to do is to put it on its own computer platform with that platform's current version of Windows, and SONAR will work, just like it does now, for as long as you can keep that platform running.
Windows updates isn't the only problem. I'm constantly buying new plugins, new virtual instruments and efx, as I think a lot of Sonar users do. So what happens in a couple of years when technology continues to advance and we'll start seeing more and more plugins that either won't work in Sonar, or more likely cause it to crash?
Right now I have occasional crashes in Sonar due to Izotope's Ozone 8. I'm betting Ozone 10 or 12 might not even work with Sonar.
Sonar will keep working if you isolate it on an offline machine, and don't plan on buying new plugins in the future.
Meanwhile all the other DAWs that are still being supported, or new ones that have yet to be created, will continue to improve with the latest technology and eventually make Sonar Platinum look like something from the DOS era.
It's like thinking your car will last forever without having to be serviced.
And just FYI, I love Sonar Platinum, and will continue to use it for the time being. But I'm also actively looking at DAWs and deciding which one I will have to eventually switch to.