Hey @HerbertFreir,
I've randomly come across this post.
It's a common thing in pretty much every online game that people will flame each other. All it is is a coping mechanism so they must not admit they made a mistake themselves. It's really just the easy way out for being anonymous on the internet. There is no way of saying this is common or uncommon across a community as a whole as it's mostly invididual. Estimating how often it will happen to you is nearly impossible. Sometimes you will be flamed three times a day, sometimes it won't happen for two years straight. But there is a tendency: The bigger and the younger (on average) the community the more likely it is that people will flame, as they don't expect to bump into the other one ever again. FAF is a small, "well aged" community, and therefore less likely to be that way, as you for sure will bump into someone again.
What usually helps is narrowing down the amount of anonymity to a minimum by playing with people you know through joining smaller clans / communities.
I, for instance, happen to run a beginners group within the FAF Dojo. It's me and my co-trainer running training sessions with up to a dozen trainees (0-1300 rated) three times a week, in the EU evening hours. Our youngest trainee is ~20 years old, our oldest is ~60 years old. We have gay / trans people, furries... We welcome everyone and respect each other. It's about having fun and learning together.
If the above is appealing to you and you could make (some of) the training hours, feel free to join our Discord server and reach out to me. If you can not make my specific training hours, please still feel free to join, meet people you could play with, and maybe find another trainer that matches your time zone. 
