Actually, both.
You should grow a thick skin, as most places where you can learn the most about big scale tech (ie. tech giants) will have rude bosses. Right now we canʼt do much about it; if you work there, you need to be tough.
However, when you leave such a company to start or join a startup, you should remember all the bad things, become gentle and mellow, and keep that attitude during and after the growth phase.
My thick skin i grew during my tech giant days helps me a lot when our startup starts working with big companies as i learned how to communicate with such bosses (i intentionally not writing “leaders” here). Meanwhile, with our employees we try to be as gentle as possible, while still keeping the (often short) deadlines. Behaving this way makes our employees more enthusiastic about their work. They tend to do a better job, as they actually care about the code they write.
Learn and apply toughness when you must. But put an example before others by being a good leader instead of a pushy or rude boss.