I'm not quite sure what the argument you're making is - on the one hand, you're agreeing that there's a difference between the treatment of "Eastern Continent" goblins and Western Continent lizardfolk that may mean something, but on the other you're arguing that the reptilians are more-or-less a marginalized minority within human society.

Although I don't think that second point really stands up - Malack is the high priest of his religion, at least in the EoB and possibly continent-wide; the "lizardfolk with the monocle" is the ambassador from the nation of Reptilia - suggesting that there's at least some kind of specific cultural identity among the reptilians - and judging by the rough proportions of lizardfolk/kobolds to humans in the settlements and groups we've seen, it looks like humans are just the majority (as is general for D&D), not that lizardfolk are specifically oppressed. You may as well argue that "Eastern Continent" halflings are a marginalized group.

Also, this whole subject is kind of off-topic - I might make a separate thread for them.