I don’t know if this is a totally true statement, the TMBR This-A-Way That-A-Way was pretty popular this year and alot of the offerings were sub 50g. My standard Walnut is 39g.
I think it comes down to the actual throwing. Lighter fixies require more finesse all around, and not everyone is patient enough for throw soft. Last week I was throwing my Play Simply and that is one of my heaviest No Jives at 59 grams.
Its a different experience. Some days I can throw heavy, but I’ll feel it the next day in the elbow. Then I’ll throw light. I have also noticed throwing light hard can feel awkward and cause some elbow pain as well as its more of a snap of the joint. It really comes down to technique. @edhaponik says it in his YYE tutorials, “Throw for the Trick” and not all tricks need full gas, but some guys are just always full throttle.