People who do commonly rely into these signals are the ones who don't like to bother or hassle themselves on making
some analysis on their own that's why they decide for easy follow signal trades.Let them be and when they lose
money they will realize things on the end.
'Smart speculators' can also use them to find which coin will get pumped by some group. If they can time it right (or maybe use a bot to do it), then can get decent profits. But it's really tricky because some group/channel only forward message from other group.