Thing is 2M doesn't quite get you as far as you think. You get 10 devs (let's say, 4 programmers, 4 artists, 2 designers), pay them 100k each (which is lowballing it in med/high COL areas), and work 2 years. That's 2.4m just from labor, before advertising and other duties like community outreach. Sell for $30 (which is basically the top end of an "indie) and you need 80k copies to break even, more after platform cuts.
That's definitely a scale a AAA studio can afford, but far from what we associate "indie" with in our heads.That's where the exploitation begins.