It's like this:

It's competition. Yoshi P himself said passions can run hot in competition. If rank points, or the potential to lose them are on the line, people are going to come ready and give their all. If you aren't ready or don't give your all, that can spike frustrations quickly.
There's nothing wrong with being new. We were all new once. Some of us learn quicker than others. Some need guidance.
PLENTY of us are willing to help new players learn, but when it comes to an actual ranked match, that is not the time or place to come looking for lessons.
There are plenty of guides available all around as well. You owe it to yourself and future teammates to do your homework.
Insults are uncalled for, yes, but you are entitled to nothing here.
You make the effort, and others will be willing to help you along. But expecting others to pick up the slack when you're unprepared is asking to have a bad time.