Not unreasonable! I’d say it’s pretty nice that he gave you a response! Often my T wouldn’t respond to my emails at all and then in session she’d address the content. I think a big challenge with email other than the privacy thing is that it’s difficult and time-consuming for a therapist to provide their services through email, especially for something as big as “I don’t trust you.”will ask him if it's ok to email...
As far as the difficulty of saying things out loud or bringing things to their attention while in the room with them? That’s often the lion’s share of why you are even going to them in the first place. It can take years for important stuff to bubble up and trickle out while in session, but the pay off is grand. So while it may seem like a monumental task (it is! And there are often multiple mountains to scale) working toward that goal IS the work.
“boundaries.. said i can bring stuff in writing in session time.”
A sign of a good therapist is good boundaries—evidence that they have experience!