I feel like the Topre price issue might actually be, in part, a marketing problem. No matter how much better the switch is than your typical contact-based rubber dome, if it were sold for less, would they be able to convince people with no interest in typical dome switches to try them?
Bit of a case study...a while back, Noppoo released a version of their Choc Pro keyboard with a capacitive dome switch. It didn't use a spring for sensing, but rather represented a revival of the old "foil and foam" capacitive sensing technology-- which, perhaps, might not be quite the same, but is still a form of non-contact-based sensing and could be expected to carry the advantages of such. The domes were individual, rather than in a sheet, and placed under some rather fancy-shaped plungers (which featured the Cherry compatible "plus and ring" stem design used by previous foil and foam switches). Pricing was set to be the same as other versions of the Choc Pro, with marketing continuing to call it a mechanical keyboard (which is a designation under which many will include Topres).
And how did people react to this? Well, you had lots of people, none of whom seemed to have tried it, crying out "OMG RUBBER DOME DO NOT BUY" and "Noppoo is a horrible, dishonest company for trying to foist such a thing on us". Sales were low, if significant price drops are any indication, and the the capacitive version was quite quickly discontinued (or allowed to disappear from TaoBao, at any rate).
That case is the closest I can think of to an attempt to make an affordable Topre, and it seems to have been quite a disaster.