that is not what sentiment means!
the real sentiment is seen in the actual market and on the actual charts. everything else is just white noise like a fart in the wind. on all these platforms like bitcointalk and reddit, there are always a lot of trolls who come out of their hiding whenever there is a price drop. remember kuwakduck? these people are the ones you think are the "sentiment" and it is not the first time someone makes this mistake. that's why they keep coming back to fool you.
For sure there is a lot of bots and crap.
But we ARE getting influenced by that. There are many examples that show that also "fake" information has an effect on public opinion:
look at propaganda in the 1930s 1940s, look at the rise of PR (just google the relationship between Freud and Bernays, the founder of PR) or the last US election.
The stories we read and hear do form our opinion even if they are faked or even if we know they are not true (recommended reading: "thinking fast and slow" by Nobel Prize winner Kahnemann).
However, I admit that taking action based on sentiment is a whole different topic.