The people who cause the problems are always the ones to first point the 'toxic' finger
Toxicity has been given too much credit as an excuse.
I'm not really a toxic person unless people ask for it. I point out flaws and how to fix them, but i dont call people names until the last straw.
Saying "Hey I am getting camped top, can you do something about it" is not toxic
Later saying "Ok, if you aren't going to gank top can you counterjungle the enemy team or gank another lane" is not toxic
When you still have done nothing, saying "Can you do literally anything other than be afk in fountain" is not toxic.
This is just an example, but that guy is the first to immediately scream that you are toxic as an excuse for their poor play. When they play poorly, and you give them advice, and they dont change, then continue to play poorly despite knowing what to do, the burden is on them. You have the right to be upset about them.
This doesnt mean you need to tell them that their mom is a whore, but riot has seriously given the 'toxic' excuse too much credibility.