I am a PhD student in cryptography, and judging by the papers I've read there is plenty of support from cryptographers, many of whom are directly involved in research and development. Silvio Micali is practically a founder of modern cryptography (and Turing Award winner), and he co-created the blockchain Algorand. There is also plenty of opposition, as the subject elicits strong opinions, but the assertion that cryptocurrency has no support from cryptographers is just false.