Scammers don't have to give huge promises anymore, believe me they are among us and they know how smart investors have become too, they always reshape their tactics, now projects don't have to give too good offers because they know people are aware that too good to be real offers are scam, honestly scammers are not idiots
People keep saying good projects always have good team and brilliant ideas to solve crypto issues, who tell you that scammers can't deliver all this?
That is true, if they aren't smart enough they won't or can't be able to scam anyone but to succeed they need to play along as well. Also, in another point, you are right that they are within us, they learn, listen and take note of everything then work on it for their own benefits. However, I do not totally agree with your last paragraph; they can be smart but will most of the times have a flaw thus the thing is finding that flaw. Nevertheless, all the time we need to be at alert and ready while learning more on how to protect ourselves from scams as well as scammers.