Hussar
Legend
Just to give an example where I believe that DM inflexibility about the setting hurt enjoyment at the table. Years ago, I was playing in a 2e game set around the Keep on the Borderlands. Fairly new group, and we're all just kind of getting to know each other, so, pretty light fare.
I ask if I can play a forge cleric (this was to become my absolute favorite PC, Korbach, who I've played in a few different campaigns under different DM's and different editions - this was his first iteration) who was an itinerent armor smith using the 2e NWP rules. The DM okayed it and off I went - spent the NWP's to be a proficient armorer and set about establishing a forge for myself and whatnot.
"Ok, I guess I want to make a suit of plate mail for the Castellan," I said to the DM in order to gain favor.
"Oh, plate mail doesn't exist in this setting. It's too advanced," said the DM.
"Umm... pardon? Plate mail predates pretty much every other PHB armor by a centuries. They made plate mail out of bronze"
"Nope. No plate mail. It's historically wrong. We're before plate mail."
"Err, how about banded?"
"Nope. Nothing better than chainmail. I'm running a historically accurate game."
So, now I'm completely baffled. Because the DM is absolutely convinced that she knows her history, I can't do something that should be no problems. She absolutely would not bend, nor would accept any contrary evidence to the history that she KNEW. Should have been giant warning signs because if the DM is that inflexible about something like that, what else is going to be a problem.
Spoiler - the entire group revolted a few sessions later and dumped her as a DM.
I ask if I can play a forge cleric (this was to become my absolute favorite PC, Korbach, who I've played in a few different campaigns under different DM's and different editions - this was his first iteration) who was an itinerent armor smith using the 2e NWP rules. The DM okayed it and off I went - spent the NWP's to be a proficient armorer and set about establishing a forge for myself and whatnot.
"Ok, I guess I want to make a suit of plate mail for the Castellan," I said to the DM in order to gain favor.
"Oh, plate mail doesn't exist in this setting. It's too advanced," said the DM.
"Umm... pardon? Plate mail predates pretty much every other PHB armor by a centuries. They made plate mail out of bronze"
"Nope. No plate mail. It's historically wrong. We're before plate mail."
"Err, how about banded?"
"Nope. Nothing better than chainmail. I'm running a historically accurate game."

Spoiler - the entire group revolted a few sessions later and dumped her as a DM.