The thing about the Grammy awards is that the majority of people who vote are:
- Older than most music lovers
- Whiter than most music lovers
- Are only allowed to vote for the best album
So in the case of Beyoncé, her videos are what made the most impact. That Lemonade video deserves every superlative heaped on it as it is triumphant. But her singing and her music are strictly in the R&B/Urban/Hip Hop/Black area of music, which is harder for the older, whiter, voters to get behind. While Adele is someone they can understand easily, because those voters want interesting and challenging music, as long as it's not too far outside their comfort zone.
We also have the dynamic of Black music being a place where Black people go to express themselves outside of White culture. Some of these acts go out of their way to make sure Whitey feels unwelcome, uncomfortable, and the outsider in the way that Black people often feel everywhere else in America. And there's also the history there of a Black artist being so good that they get coopted by White culture even when they want to keep them at arms length.
And that's the problem with the Grammies or most of those artist awards: it's supposed to express everything that is excellent in this year's music, but it's ran by the establishment which is mostly white still. So Black artists are often in a situation where they crave the recognition they definitely deserve but they also use their music as a way of expression that they don't get elsewhere because they are outsiders in mainstream culture.
So was Beyoncé robbed? Yes, but awards are bullshit anyway. Especially for Black artists who are either forced to conform or be coopted by White culture. Or they're forced to stay out of the mainstream, which means they will only get the recognition they deserve from White culture years afterward when the oldest and whitest of the voters have moved on.