what is the point of making it an omegaverse if it has no relevance in the story?/g

Maybe so it'll be tagged in a way that gets more views/clicks?

Or maybe because some people might find the story sexier if the higher class character (parading as an alpha) is actually a lower class (omega)...?

But IMO, the omegaverse trope is optimally applied to call attention to the ridiculousness of societal gender norms / inequities.

If the intent is for fans to get off on the concept of "taking someone down a peg" or "someone getting put in their place", but the author decides to bring sex/gender into the fold, it can actually make it less appealing to many liberal-leaning, critical-thinking people unless they secretly feel turned on by the opposite of what they promote IRL (e.g., like if an openly misogynistic dude secretly watched dominatrix pr0n—since this particular work screams 'hentai' louder than 'BL', I assume that's what the author was going for).

But for more conservative-leaning / minded BL fans who prefer when omegaverse works portray feminine-coded characters as physically, mentally, and emotionally weaker than male-coded characters and who get turned on by the idea of the former being naturally more submissive to the latter, I imagine this author's work would be equally (if not MORE) disappointing, since those fans tend to enjoy the borderline barbaric* concept of hormones causing alphas and omegas to lose control of their executive functioning / ability to self-regulate their behavior (*NOTE: I say "barbaric" because IRL, if a man got so turned on by a woman that he SA'd her, he'd be perceived by most civilized societies as a brutish criminal, but in many omegaverse works, the world building establishes that society would blame the omega for failing to keep their hormones in check/driving the alpha to give in to primal instincts).