I'm sorry, but this is completely wrong.
First, there is immense amounts of competition in video games; the industry is bigger than ever but there are so many companies and even small fry indie shops can make it big with talent and a bit of luck.
Second, there are tons of GTA/Doom/CSGO/sports games clones, licensing notwithstanding, that fail for various reasons that usually boil down to "bad game." Brand popularity matters, sure, but many studios blasted their way to huge sales and fame through having a damn good game, like Minecraft, Terraria, and Rocket League, to name a few.
There's so little barrier to entry in the gaming industry at the moment. If you make a good game, you will generally get tons of sales.
I wouldn't necessarily say "make good game get sales", just because there are a fair amount of devs who don't get marketing right, but the point stands.
Monopoly doesn’t just mean “this company is bigger than I’d like.”
As evidence of what I'm talking about I also cite the absolutely huge number of "indie" developers, the vast majority of them not being the ones you've heard of, because most of them aren't famous and face sales figures in the hundreds, if not dozens. Many of them are actively taking a negative salary (that is, burning somebody's savings) to work in the game industry.
People make weird career choices for the perception of prestige or being able to call themselves part of a team. I got a friend who is an Agricultural Mechanic who works for some local owned companies. A few years ago John Deere built a facility nearby and you'd be surprised how many mechanics, who by all accounts liked their jobs, moved to work for John Deere for less pay, less benefits.
Video games aren't that much different. People will harm their own career goals thinking they can work for a brand name when an unknown company might have a better fit. I'm sure they have valid reasons for making the decisions they do, but from the outside looking in, it just looks like fanboyisms.
Successful games tend to get purchased by larger companies, but there are a lot of large game companies. Valve, Epic, EA, Nintendo, Sony, Rockstar, Activision Blizzard, Ubisoft, Bioware, etc. And that's not even getting into mobile/Facebook games, which are easy to speak derisively about, but are still major players in the game space.
Game companies are about the most-diverse and least-monopolistic of all media we consume.
The main reason is that there isn't enough competition. Video Game Companies are pretty much in a monopoly. No one is making a game like GTA. No one else is making a football game (You need the license), No one else is making doom. No one else is making Counter Strike.
Games became brands. The only thing that drives you out of business is your own greed of recycling your franchises/ideas.
Oh and also many of those companies do not need that many of the "expensive" devs because many of those video game companies are using middlewares like unity or unreal engine.
With more competitions better video game companies would hire better engineer at better salaries. that will lift everyone else.