Maybe provide a button in Windows to flip the OS … make WSL the base OS and cram Windows into a (sandboxed) subsystem; a Linux Subsystem for Windows (LSW).<p>Kidding aside, robcohen makes a great point about the infinite backwards compatibility … if MSFT were to sunset more product versions more quickly it could accelerate upgrade cycles. But then again “new code considered harmful” applies.<p>What could help is a much more modular OS that installs a very slim base set of functionality and lets users choose additional capabilities to install or not. This would (perhaps) cut vuln and misconfig surface area if it were implemented in a real way.