Good GMs are fairly hands off, down for a joke and delegate properly. My imperial GM does this well, all reprimands and important stuff is officer chat or /w, helps people out, answers questions but doesn't interfere with how they play and only steps in on gchat arguements if things get really out of hand.
Bad GMs are exactly like you describe it. I recently had such an experience with a bad GM, where I talked over him once in TS and he gkicked me (while I was offline as well, didn't even tell me over TS or do it while I was on, classy)., he kicked another guild member in the 5 days I was there because she had to go calm her crying kid down in the middle of a story mode ravagers. No wonder his guild has at best 6 active members in the middle of the day.
However, in general, I would say most of the larger guilds and more established guilds are quite well managed.