Hmm!!
Hard to believe that, bro. A quick forum wide search already shows me posts about UVB from 2009.
https://www.rollitup.org/t/to-uvb-or-not-to-uvb.229101/
So this is nothing new and the first research in this area were made in the 70's.
Instead of talking about it for 2 years you should try it. The things are not expensive; a 24w bulb with ballast and reflector you can build yourself for $30 and if you are lazy you can take a ready to use T5 fixture for reptile bulbs you get for 60-70 $.
UVA/B have become interesting again because spectrum tuning with LEDs is so much easier. We can communicate with the plants now by using specific wavelengths to trigger certain behaviors. T5/T12's are only used because there are no UVB LEDs to date that are durable enough and are not 10x more expensive in the same time.
A 24w/2ft reptile bulb hanging 12-14" above the canopy covers already a 2x 2' area and the more intense Agromax/Solacure bulbs cover even more surface area because they need 16-20" at least to not harm the plants.
I have two 24w bulbs running 3 times 25 minutes. Thats 1,25h or only 60w per day; for a 70day cycle that would be only 4,2kwh. Even with reptile bulbs and 8h the day it would end up with only 30kwh more. So its not a huge cost factor.