Not irrational at all. I've gone through countless newer keyboards, both insanely expensive mechanical gaming and business, yet none feels as "right" as the M.

Not irrational at all. I've gone through countless newer keyboards, both insanely expensive mechanical gaming and business, yet none feels as "right" as the M. I got it new for a pittance in the 90s. It may weigh almost as much as me, and look a little grubby, but it seems destined to remain in mint condition forever. If it had a few media keys it'd be perfect. Keyboards and trackpoints are why I stuck with Thinkpads for years, and despite owning several always hated Macbook keyboards and touchpads. It's also why I was deeply offended when Lenovo replaced the 7 row keyboard with the compromised 6. When I spent a lot of time on iMacs I had a mechanical that was similar to the old extended keyboard (though not as reliable). So no, as the main interface to a machine, having a good keyboard with adequate travel is hugely important, and not the least bit irrational.