But looking at other thread about puzzle, cracking or brute-force Bitcoin, i notice many low-ranked account make reply on such thread.
That's what makes it suspicious. They are not just random newbies but accounts that haven't made a post before that thread.
Of course, shillers has also made progress and is doing it a little more sophisticatedly compared to the former "good project" posts. Over time, they learned how to avoid easy recognition of this way of communication.
Finally, there is an open offer for this type of service, easily accessible to everyone
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