Note that SIKE is not a digital signature scheme, it's for key exchange. Hence SIKE cannot be used for signing Bitcoin transactions but can be used for encrypti

Note that SIKE is not a digital signature scheme, it's for key exchange. Hence SIKE cannot be used for signing Bitcoin transactions but can be used for encrypting communication over the wire. For digital signatures, the 3 standardized schemes are Falcon, Dilithium, SPHINCS+. Falcon/Dilithium can be used in blockchains though they are much larger compared to elliptic curve ones. SPHINCS+ is way too large. There is likely going to be a newer NIST program for signature schemes with smaller signature size.