The problem I see with bullet manufacturers is that they don't give a shit because the mathematical models they use don't differentiate between bullet designs like wadcutter,flat base,spitzer,round nose semi Spitzer etc.etc.etc.
They assume one drag function and run with it.
G1&G7 just happen to be the most popular rounds that's why the data for G2,G5,G6,G8,GL is hard to come by.