Saying people need thicker skin is just asking for them to care less about what people have to say.
If we were to care less about what players think and feel, why waste time engaging in the first place?
I guarantee even digitally stone-faced Rioters feel burned out after sorting the character attacks from the useful, thoughtful feedback. Feeling nothing is not the norm.
We could gather sufficient feedback on products through surveys and player labs. We don't need to talk to communities online to be able to do our jobs.
Rioters choose to do so because it feels like the right thing to do. It helps players feel listened to, it helps them feel that we give a shit, and every now and then you get a gem of feedback that we've actually not heard or thought of already that levels up a product.
We care about how players feel, that's our curse. But we're people too and for some Rioters who literally break themselves for the community it's hard to feel like no one cares about how you feel too.