I believe some of the confusion here is the conflict between older and more current versions of development updates. There was initially like 8 developers but the list shrunk since February.
Right now I am almost certain it's just
Thies1965
UtopianFuture
LoiTran4
Krysto
Makoto1337
5 x 60 = 300, 300 being 10% of 3000.
As you can see - this is still 10% of the 3000 stakeholder figure or 1.8% per development of total NEM in circulation (3000 + 300 development stake). As others had implied, if you wanted a piece of the Pie then you could had contributed between the months of February and April.
As for comparisons with other examples - I think they are all valid comparisons. NxT, Mastercoin, Ripple, all had pretty lopsided distribution.
Maybe you have mis-read NCC specification. NEM core development team currently are
UtopianFuture: organization, technological road-map
Jaguar0625: core developer, NIS, NCC
Gimre : core developer, NIS, NCC
Makoto1337: core developer, NIS, POI
Thies1965: core developer, NIS, NCC
BloodyRookie: core developer, NIS
Krysto: NCC, web developer
TranLoi: NCC, designer, UX element
working parallel on two products NIS (Nem infrastructure server) and NCC (Nem Community Client) and of course a bunch of other things.