If having a negative opinion about a stock was illegal then having a positive opinion about a stock would be illegal too, and nobody would be allowed to mention a stock at all.
Your hero, George Sharp, has plenty of negative opinions about stocks: LTNC, CDFT, CUBV, SANP, PTTN (a little while back).
And honestly, he is right about all of them.
So, it's not that somebody is sharing a negative opinion that bothers you, it's who is sharing the opinion and about which stock that bothers you.
Think about that a little bit. Take your time.
I've said in the past that I expect GVSI will turn out favorably for Sharp.
In my opinion, RETC was a dangerous and stupid mistake.
I don't care who buys or sells RETC.
But you better believe I'm entitled to my opinion about why I believe it is dangerous and stupid mistake, whether you like it or not.