I suspect that easily accessible compression has had an effect on the value of reprocessing.
I have seen it the case that the refined minerals take up more space than the raw ore does, and with quite a few industrial ships having dedicated ore holds that can carry this compressed ore, but not the refined minerals, the logistics of transporting compressed ore is easier to solve.
For those with access to facilities in lower security systems, the enhanced efficiency of those facilities makes it more lucrative to buy the ore and transport it to the refining site than it would be to potentially purchase minerals from someone who did their refining in highsec.
Some modules that drop are worth throwing into the reprocessor. Particularly the warp disruption field generators.
Also, Highsec now has moon mining that can produce some of the mineral types that were much more limited prior. As it is possible now to get Arkonor, Bistot, Crokite, and Spodumain in highsec systems now, minerals that were rare before are not as rare as they used to be, which would lower the value of scrapped modules that were previously a more significant source of that mineral in the region.
That’s my gut analysis. Market forces are complex and dynamic and, most importantly, not my forte, so take from it what you will.