Time limit to re-enter dungeons

[Betelgeuzah]

This i would stop playing right away.
Drop rate should be equally , and personally ill dig with long cool downs but not with salvage type drop rate.

So hardcore will get their stuff 1/2 too fast as before, get bored and quit, while the casuals take 1/2 too long to get their stuff, get bored and quit.

Yay for the middleground!

That is speculation. Most hardcore players got at least a month out of the top tier NMs. Some got longer.

It's not speculation that a part of the playerbase SE wants to keep will make good use of the 5min cooldown while others are the opposite.

It doesn't matter what X (how long it takes to clear the content) is. What matters is how long the devs intend the content to last, and how hardcore population will take less than that time to finish it, and the opposite for casuals. Two hours, a week, a month, 3 months... Whatever.