I mostly agree, but... Even though the quality of the cheap basses are fine nowadays, they often use different wood types, have slimmer necks and inferior pickups. Not to mention super thick finishes, that can dull the tone quite a bit.For me, the quest is almost a contradictory one...the P-bass was/is a utilitarian instrument, where diminishing returns set in quickly. For me, the sweet spot between utility/quality is a CIC Squier CV '60s or a Matt Freeman. Or if it must be a Fender a MIM 50's/60's... YMMV.
That said, my main bass since many years is a heavily modified Squier P that I chose because that specific sample sounded incredible. The other identical ones in the store didn't.
IMO the likelyhood to get "good" wood pieces are greater with the more expensive models. But if you have the opportunity to try the bass first, check out the cheap ones as well.
Oh, and of course there are duds among the expensive ones too.