Aren't you seeing it backwards? Other professions should have the same "luxuries", in a humane working world. Instead people are treated like cattle.
IT being an "amazing productivity" boost, means those "divas" you describe just get small part of the value they create, especially since a heck of a lot of the rest ends as unprecedented profit levels...
Under a capitalistic labour market theory, employees are not and can't be "overpaid" (and surely not for decades on end). They are paid exactly what they are worth, as price is based on supply and demand equilibrium.
Under a marxist labour market theory employees still can't be overpaid if the company makes a profit on top of what it would re-invest in itself (infrastructure, etc.).
So, under neither theory workers can be overpaid under any normal circumstances.
At worst, under capitalism there can be a higher market rate that gets adjusted to a lower one, but at each point in time none of those was "overpaid", it was the best the market knew to set. The higher rate was appropriate supply-and-demand-wise for when it was applied (and it might raise again as IT companies compete for developers, and so on).
Let's not forget the "US/Europe needs X millions more developers" reports churned out every few months...