Earlier quoted context omitted.
I regret getting rid of two Model M's several years ago because I didn't know about the bolt mod. It's not irrational to spend a lot of time maintaining a tool that helps you make money. I'll hold on to my current M forever, if it'll last.
It does cross into irrational territory though when you can make money with an equivalent tool.
Plus, our profession requires enough creativity to be compared (loosely) to art. An artist's tools need to feel a certain way to evoke the right state of mind for creative work.