This is hypothetical, and based purely on the idea that gods are ascended beings/mortals. We're assuming here that human beings are capable of ascending to godhood, which is where the discussion could come in.
My thoughts are, if ascension to this higher state is possible, and that is what (at least some) gods are, why shouldn't we strive for godhood? I can understand that arrogance is destructive, but in consideration of the whole concept surely it would make sense to work towards and encourage aspirations for godhood, rather than shunning the idea that mortals can become gods?
Then, you also have the whole "mad with power", god-complex issue. And I suppose just trying could be enough to drive someone mad.
But I often see or hear of the idea of striving for godhood shunned and seen as arrogance, rather than as a legitimate spiritual aspiration. But, why? I'm more curious as to why this aspiration would be a bad thing, other than for the previously listed reasons.
I'm not looking to become a god(dess), of course. It's just more of a shower thought. And I'm sorry that this discussion does make a few leaps and assumptions, but working with those in mind; what makes aspirations to godhood necessarily bad?