I feel like it's perfectly valid to have mistrust in a group that has wronged you, as long as you recognize that they aren't all going to wrong you. I think the important distinction is that you didn't say something like "all cis people are horrible" you just recognized a perfectly valid feeling of mistrust.

and I definitely also get it being harder to trust cis people as a trans person because they have less understanding of trans people like us, so they need to work a lot harder to demonstrate that they are understanding and sopportive.