Accidentally misgendering someone is not harassment.
Intentionally doing so is. Because that’s the whole point of intentionally doing so.
It’s really not the big effort you seem to think it is. If someone looks like a man to you, you refer to them with masculine pronouns and if they correct you, you apologize and go with the pronouns they prefer.
The point is that you don’t keep doing it when they tell you that you’re using the wrong pronouns.
Why do you think people should only care about what you care about and not care about the things you don’t care about?
You sound like you come from a position of privilege and have not been treated with the maliciousness and even violence trans people have to deal with on a daily basis.
I suppose asking you to put yourself in their shoes would be too much?
And as I thought, the issue here is that you yourself are a bigot.
Why not toss other queer people into that category while you’re at it? Are gay men are no different from bronies and furries and they should just tolerate being called f*s? Or are those disgusting trans people that make you feel icky the only people who get harassed and attacked for their immutable characteristics that should just suck it up and take all the hatred thrown at them?