i think that's why boundaries are so important. certainly there are is an abusive minority that exists that use that ability to manipulate to gain something they want (power, etc), but that's where knowing the boundaries can be helpful - so you can recognize the red flags.

my t is super friendly and so in our five years together there have been yellow flags here and there, but they turn out to be nothing, just miscommunication. that's how i protect myself though. and for me, i also do group therapy run by different ts so if he did something i was uncomfortable with and couldn't talk to him about, i could go to someone else.