Unfortunately people who will not speak up out of fear are toxic to company culture. The creative process is immediately destroyed when people need to second guess everything they say or do since it is impossible to know if you are about to say the wrong thing.
If someone can not tolerate cynical and sarcastic comments they need to be removed quickly. This is very different from mean spirited put downs and intentionally hurtful comments.
Stuff like "idk that button looks like it was mad in 2002" or "I swear we have the shittiest parser ever right here". Is good and fine.
"You talk to much", "why did you write it like that? It doesn't make any sense" Are bad.
Notice how the first like says "we" or talks about a specific feature and the others talk about specific people.