Are hasted bosses reasonable in the end game?

Granted, this is not a problem for 1-button range builds - but I'm not interested in playing 1-button builds.

I just question whether or not this mechanic of monster haste is even reasonable. Nothing is balanced around monster haste, as you elevate the difficulty in maps unless you play a one-click range build these types of encounters begin to just rely on probability - "I hope the boss doesn't do this one mechanic in a situation that's totally unfair."

For example, the Lachdanan fight (or Colin, or whatever his map name is). If you give this boss haste, certain mechanics are elevated to impossible-to-avoid one-shots (eg. 'my rage burns'). There is no viable counter play - you just die if you're in melee range.

Now you might say, well don't take haste into a boss fight. And yes, I agree that is one option.

However, haste can be given as a monster difficulty modifier, so as soon as you have 2 atlas points in bosses, you have the chance that the boss will be escalated to a haste boss. Any other boss difficulty modifier is basically a chance to be a haste boss.

Am I meant to log out? What's the strategy here? I think it's clear the boss mechanics are not balanced around haste. When you haste bosses, many of the mechanics become impossible to counter.

Bonus mention for expedition 'blue and red circle of death' which is an equally unavoidable 1-shot mechanic that becomes unmanageable with haste.