I think the challenge with 10 IoT LTSC isn't going to be the OS itself, but the software running on it. Lots of software uses chromium embedded, and in the case of win7 the day that extended support (+3 years) ended CEF also dropped support and required features only found on more recent windows releases, then as other software updated their CEF dependency they also dropped win7 support. It might not be a major thing, but there is a slow erosion that goes beyond whether the OS gets patches. If nothing else, if it's a machine that uses software that goes online it's a notice that you should investigate moving to something else eventually.
Win10 IoT LTSC does not cover all use cases though.
When it comes to gaming, for example Windows Mixed Reality is not included and cannot be installed afterwards (but then again, Microsoft dropped it from Windows 11 too, so no loss there).
Only way to keep it is staying with consumer Windows 10 or use 3rd party software like Oasis.
Problem with 10 LTSC is the fact that it's based on 21H2, and there definitely isn't going to be a feature update for it, now that 11 LTSC is out. Some games already require 22H2.
If you practice good operational security and maintain a decent anti virus and fire wall you will probably be fine. I know people who still run Windows 7 to this day with no trouble because they are vigilant of what they are doing.
This isn't to say it's a good idea but that it can be done.
If you plan on running win 10 anyway Ask Leo has a video called "how to keep using windows 10 safely after support ends" with some solid advice
While you're at it, you might as well downgrade to Win7. No jokes aside, if all the software you want runs on it, it is fine. Just no security update etc.
I would suggest just switching to Linux and using a VM for things that NEED to be Windows. Games that run kernel level Anti-Cheat won't run, but tbh nothing I would suggest installing anyway.
The big two that spring to mind are online games and Adobe softwares. I don't think a VM can usually meet the performance needed for either.
I do wish more artists would take a chance on open source softwares, but most of the ones I know are still insistent that nothing can ever come close to Adobe. But that's a rant for another time.
Games run pretty great on Linux, but if you do want a VM, passing through a graphics card to that VM via vfio provides 95%+ the performance of native.
Virtual reality headsets with dual 4K screens running at 75Hz+ perform well on a Windows VM done that way. A normal flatscreen game is going to be just fine.
I stayed on Win7 until December 2023, until there was some exploit that was attackable by just viewing an image, so just browsing the web would've made it vulnerable (I believe in the WebP format).
Although it seems there are people still Frankensteining Win7, and even patching DLLs to make the newest browsers/apps still run on it.
Famously MS Teams was really screwed up, but I had to use it for work..
The problem is not the lack of patches. The problem is with websites refusing service based on client's version from the user-agent or breaking by using cutting edge features without a polyfill.
