proof of work is a good measure against DoS attacks, but not against low to medium volume spam.
SHA256 in particular has hyper efficient GPU/ASIC implementations. set the difficulty high enough to hang the browser on an average phone or a laptop for several minutes, but a dedicated spammer can just rent the hardware to solve those in fractions of a second very cheaply
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[ 2.9 ms ] story [ 20.8 ms ] threadSHA256 in particular has hyper efficient GPU/ASIC implementations. set the difficulty high enough to hang the browser on an average phone or a laptop for several minutes, but a dedicated spammer can just rent the hardware to solve those in fractions of a second very cheaply