Yeah, macOS 7-9 had known weaknesses (e.g. burning CD coasters or skipping audio if you held down the mouse button, keeping it in an interrupt handler) but they

Yeah, macOS 7-9 had known weaknesses (e.g. burning CD coasters or skipping audio if you held down the mouse button, keeping it in an interrupt handler) but they were more deterministic and people could avoid them. The DOS-based Windows versions were just plain bad, and only Microsoft’s illegal product tying kept competitors off of the market. Windows NT 3 was at least stable, but they made it worse moving drivers into the kernel for performance in 4, and it took decades to repair the security damage that caused.