I'm not talking about dungeons, I'm talking about in general. Let's talk seph ex since that is what most people are doing right now.

Bards can slidecast with the exception of getting a tower if needed, earthshakers, and yesod (maybe, even that is possibly slidecastable, not sure). You drop WM during the pillar of might, but you can keep DPSing freely without a break, melee have to try to position to keep hitting the boss while this goes on, which means watching the vuln zones while staying in melee while doing your rotation and not standing on the blue marker. If you get orange buff, you can keep attacking from the safe spot on either side, which means you have time to slidecast to the tower the 2nd time. None of this stuff is hard.

Melee on the other hand need to stay at the edge of the vuln zones/kill slots til the last possible second to max their dps. They lose attack time while being punted around. They lose dps time during earthshakers in order to get far enough away from the boss to not die. You don't want cooldowns up during orange buff because you'll have to stop swinging for a few seconds when the vulns are at their largest. You have to spread for da'at because unlike the ranged who can back up and have 3/4 of the room to themselves, you all need to be in melee.

I'm not trying to paint the picture that ranged are easier in general, I just don't think they are harder either. You have more restricted movement but generally have way more space to yourself, and by planning properly can have less downtime in some situations than melee. Saying that melee "just stand there and do their rotation" is pretty simplified and not the reality of many fights.