"if you write that person off as being stupid because you can't understand them, I think it shows a certain ignorance."
Yes. It does. I agree with you 100%. Anyone who sneers at someone because of their accent and decides they are stupid is a twat.
But that's not what you said.
In either your thread title or your OP.
"If you don't understand someone because they have a different accent to you, it's just ignorant."
Is ridiculous.
Had you said If you tell someone they're stupid because they have an accent ...
Then you would have found very different replies.
and your OP "And maybe a little bit stupid
I know some accents are difficult to understand, but fgs try."
Had you said there what you said later on - then the response to you would have been very different.
The impression you gave by your choice of words is very different from the situation you went on to describe.
It's not just about accent, this communication lark 