Of course, these matters are complicated because there are other dynamics at work too. There are some fairly nuanced distinctions - a lot of gangster rappers didn't see Will Smith's family-friendly rap as selling out because he'd never claimed to be a gangster. Among rappers a less well known performer can gain a lot of publicity from starting a feud with someone well known, so some of the criticism has mixed motives (accusing the successful of selling out is a classic choice). And if you believe all financial success is inherently inauthentic, hiphop's bragging and bling celebrating financial success might seem like an embrace of inauthenticity - but I think most such performers would say they were poor and they're now rich and that's the reality they're authentically representing.
However, it's certainly not true to say that hiphop has wholeheartedly embraces selling out, or did so from the start.
As Randall Kennedy writes in Sellout: ‘The Politics of Racial Betrayal‘, ‘When used in a racial context among African Americans, “sellout” is a disparaging term that refers to blacks who knowingly or with gross negligence act against the interest of blacks as a whole’ (2008: 5). For rap artists, commercial success or brand partnerships are not necessarily subject to accusations of selling out, as long as artists don’t use their newfound wealth to abandon the communities that nurtured them. https://www.thestateofthearts.co.uk/features/the-story-of-se...
The OP conflates the genesis of hip-hop with its commercialization. For example, the dawn of hip-hop predates the "influence industry" by 30-40 years.
The commercialization of hip hop is what transformed hip hop from a sub-culture into a market and mainstream force. A large part of that was hip hop's lyrics condemning the "no sell out" culture.
