Most games in Japan are catered towards what the Japanese want to see, so you don't exactly see a lot of white or black people in those games and, when you do, their stereotypes are greatly exaggerated (huge eyes on white people, for instance). Am I offended by that? No. That is their market and they do what makes sense.
Here are demographic breakdowns of the United States:
*These numbers may not be exact, but we can update after the 2020 census*
1.2% Native American
If a game is catered towards the American/European Market, then it makes sense for it to often, if not the majority of the time, have white main characters. People need to stop being so offended. This is simply capitalism at work.
I get what you are saying and I agree what someone else posted, that video game writers are just going with what they know. If they are white they are likely to write white characters.
Yet I would point out that video games are not perportionate to the demographic you cited. And I have seen some charts that put the margin of white in america is 40-50% now. This is not properly demonstrated in media because 90%+ is white male, not 50%. Almost all movies/video games of yesterday and today have the same exact archtype white male leads. The number of video games that put a Black or hispanic(god forbid....an asian) main character on it are very slim. Mafia III, Dishonored 3, GTA San Andreas, Just Cause, Watch Dogs 2, Sleeping Dogs and.......I think that is about it. It gets really dicey when you bring in the fact that 50% of the population is female yet still..... 90%+ of the leads are male. I can probably name more than 100 games with character archtypes as the Previewer stated.
The few games that are experimenting with diversification are selling less(except in the case of games like GTA SA), even when in a anthology series. Why is this? The quality of the game itself could very well be different but at least part of that factor is thought to be white male gamers have a harder time identifying with characters that are not on some level similar to them, or at least the pennacle masculine archtype they are used to. This is often sited as a capitalistic reason on why games do not deviate too often from the traditional. Yet if this even is the case, I would state that black/hispanic/asian/women/etc have been consuming video games for a long time, combined make up 40-50% of the marketshare, yet have always just been expected to be able to find common denominator with characters that don't look anything like them.
And then people complain about anyone wanting to see a little more diversity, not even in race....just give us some variance from the gruff white male lead. Give me a bookwormy clean shaven guy with a normal voice. Sure, it feels pandering now but developers,fans and critics alike seek to make up for lost time.