Most Forums and Communities are treating users as spammers. Why is that? I was treated most of the time by forums, is it because of my Damn ISP who is giving me a Shared IP? Just expressing something. No other reasons.
Because most of them are. 
But if your posts are legitimate and follow the forum rules, you should be fine. If you are trying to promote yourself or insert links that are not wanted, you’ve got to expect harsh treatment.
I didnt even made a post or even reply to some. Just Created an account and later boom. Im a spammer.
There are even some sites that upon registration if you use a certain email you are automatically dubbed as a spammer and wont be able to continue unless you create a new account. i really hate that.