It's not WHAT you say, it's HOW YOU SAY IT
and how good you look
!
But seriously, I can't count how many times I've seen someone complaining that they were reported for just "telling our top laner to play safe" or "asking the jungler to gank" or "suggesting the support buy sightstone". But the people who say this are completely missing the point. You didn't get chat restricted for giving advice, you got restricted for being an ass about it.
There is a world of difference between saying: "Hey [support] we don't have vision on dragon, can you ward it?" and "IF YOU DONT WARD DRAGON, YOU'RE FUKCING WORTHLESS"
It's not just about what you say, it's how you say it.
It's totally fine to tell your top laner to play safe, but "stop feeding noob" is not good advice. After losing a teamfight saying "that was a bad fight" isn't toxic behavior, but "WELL, fuck all of you, you guys just threw the goddamn game!" is. Asking for a jungle gank is actually a GOOD thing, but if you don't get one and start spamming "GG trash jungle never ganks" then guess what? You're gonna get reported.
I'm sure most people understand this, but it's common enough to see people playing innocent about negative behavior, that I felt a blanket post was needed.