Not Windows: Operating systems. We did get more capable operating systems. The point of the quote is "this is the worst the SOTA will ever be".
If Windows XP were fully supported today I still wouldn't use it, personally, despite having respect for it in its era. The core technology of how, eg OS sandboxing, security, memory, driver etc stacks are implemented have vastly improved in newer OSes.
You're just moving the goal posts unfortunately. The point is that positive progress is never actually guaranteed.