Refractors what have i missed out on?

Hey everyone I been in the hobby for roughly 20 years recently I have noticed refractors are hot at them moment.
I wanted to get my hands on a Tim Duncan Topps Chrome RC Ref and have noticed the prices are more than what I expected even a Vince Carter RC Ref can set you back $300-$500 raw

Is it because the recent releases of Panini Prizms that refractors are back in a big way or have I just been blinded by the Auto Patch stuff and have forgotten about the blinding glare from a nice looking refractor

Lower numbers of refractors in total were printed. Then they were placed in boxes from hobby years where cards were mass produced 100x more than sets today equals a much much rarer card.