Let's use a furniture analogy. Ikea makes a bunch of mass produced minimalist stuff people seem to like because it's A) Simple, B) Functional and C) Easy to assemble, D) Can be reconfigured for various uses and E) is inexpensive.
Some people like minimalism. Others want something like a automatic reclining couch with butt warmers and fold out cup holders.
For me, a P-bass is basically the bees knees because it seems to produce a well rounded bass tone and there isn't much to mess with. They're easy to maintain, reconfigure, dial in a tone, etc. It's just a slab of wood with a pickup and two standardized knobs.
You might not like P-basses because of the lack of top-end, or lack of onboard EQ, but there are pickups and pedals out there that can re-EQ your tone. P-basses can be reconfigured easily is the point.
Less isn't always more, but in some cases having less teaches you to be resourceful or to break a problem into different steps or operations. If I need some other tone I can always add an effects pedal or different amp, but I can keep the same P-bass.
I don't know, it's just the way I think. I work in a field where we break complicated problems down into simple steps (AKA programming). It's easier to remember simple things and chain them together to solve a complicated problem than it is to remember a bunch of complicated formulas or software packages/libraries that solves the whole problem at once.