I was a member of the Drama Desk for many years, so I'm well aware of how the composition of the nominating committee has changed (or, for some stretches, NOT changed). Having served on a screening and nominating committee for another organization, I appreciate how much dedication and long hours go into seeing tons and tons of shows for awards consideration. I also see the appeal, prestige and power of the task, and how hard it can be for some people to relinquish that. I knew one Drama Desk nominator who regularly complained to me about what a burden it was and the many hours of meetings involved, but that same person would volunteer again and again, to be a nominator.
The Tonys, at least, rotate their nominators with some regularity. I wish other organizations would follow suit, and give others the opportunity.