Tim Sweeney has continually dogged this line of attack against the UWP platform again and again, despite Microsoft even making changes to address his concerns.<p>1. Regular Win32 software support is probably never ever going away, because it's the bedrock of the Windows platform to this day.<p>2. Universal Windows Platform apps can be installed by third parties just like normal applications. Steam could support distribution of UWP apps if it chooses to.<p>3. Cheapy Chrome OS alternatives aren't going to be competing with gaming PCs that are the bedrock of Steam... ever.<p>Tim's pretty much flat-out refused to recognize these facts, and has been scare-mongering this point since Windows 10 came out or before.<p>UWP being a sandboxed app platform is just "better" than the legacy software design from a security standpoint. Nothing about UWP inherently makes it lock out third party distributors, it's just that nobody else has chosen to distribute them yet.