Isn’t this common knowledge that there are computers you use for banking, computers you use for windows 98 and computer you use for gaming?

For banking I use macOS/linux, sometimes iOS unfortunately but we all do sins

Most people can't afford to have multiple really good computers. More likely you have a phone plus a single desktop or laptop. You would want to share your expensive GPU+memory on the same computer you use for gaming graphics and for AI-models for development.