Are most paphs grown in lower light conditions?
No, absolutely not.... but it depends on what you mean by 'lower'...if compared to Cattleyas my response would be in the affirmative, as I would never place my Paphs in a window facing South, where many of my Catt.s seem to thrive (bear in mind I live in the Northern hemisphere quite far away from the equator - therefor not South in the sense of Florida, Texas or Arizona).
Some of the Paphs growing in nature in the underwood or as humus epiphytes inbetween the roots of large trees might thrive with lower light or a more diffuse light source.
You can often learn something from information on the natural habitat of the plants - especially informative have I found Baker and Baker's meterological data for the habitats of many Paph. species in the sadly not completed work on the genus, that they did with Guido Braem.
Averyanov, Crib et al. in their preeminent monograph on 'The Slipper Orchids of Vietnam' likewise provide data from two weather stations near to the habitat of each of the species, they describe.
There is a lot of information to be gathered from such and like data, but one has to keep in mind, that one can't always make 1-1 inferences from environmental conditions to the optimal conditions in culture. And also be aware of the fact that the data we have at hand might be incomplete, limited and somehow leave out information that might be vitally important for culture.
I think a classic example in this respect might be P. henryanum: in the descriptions of its habitat it is ever so often stressed, that it grows on calceolous cliffs, which has led growers to add lime stone to the mix to mimic the supposedly alkaline condition of the habitat. Well, some botanists noted, that instead of seeing the manner of growth for this species as litophytic, it would be more precise to describe it as a humus epiphyte, as the plants tended to grow in cracks, on protrusions, etc. where decomposing remnants of leaves, bits of small branches and other organic material gathered. One bright head took samples of the rainwater running from the humus after the rain had subsided. Analyzed the PH value of these water samples turned our to be slightly on the acidic side. So much for alkaline....!
I've, since I learned about the above information, stopped adding limestone to the growth medium, which I did for a few plants, that I thought needed it. After I stopped, I happened upon Baker and Baker's general warning about adding limestone - they wash out/dissolve too fast and skews the PH in the mix.
My friend and mentor in all things orchidiadic, Hans Christiansen of Orchidegartneriet, still - after 50+ years as professional grower - admirably and unstintingly experiments and refines his cultural methods. He has the last couples of years moved the majority of his larger multiflorals (Roths, Sanderianum, Kolopakinkii, Topperii etc.) up quite high in his greenhouse, where they get more than an ample amount of light....and with great results!