The optional content in the game is some of the best there is in it to do. I don't want to be restricted to a smaller pool of stuff to do. Where's the fun in that?

It may appear to be a staggering amount but only because a lot of the l50 and l60 dungeons were added one or two at a time per patch update. The added lore and subplots of the dungeons adds a lot to the game.

Like, one of the favorite subplots of the playerbase is that one concerning Edda. (Tamtarra》Tamtarra Hard》PotD)

Some of the best music even comes from the dungeons imo.

I suppose the complaint you have can be rectified by not utilizing that content. However, your complaint about wait times can be resolved by having friends que with you or having FC members party up. Or, use the Party Finder.