Yes, perhaps before they choose the next "faster in hardware" crypto algorithm, they also get a commitment from the major chip makers (Intel, AMD, Qualcomm, MediaTek, etc) that they will implement them within let's say 2 years after the contest is over.
Otherwise it's just hope that the chip makers will implement it when the algorithms are chosen, and I'm not sure that's good enough after a carefully orchestrated 5-year process of choosing a next-generation algorithm.
If they can't get that commitment, then they should choose whatever is faster in software (granted all the other factors are more or less equal).
Most things are software; from previous experience we know that it basically takes 10 to 15 years between introduction of a primitive (AES and SHA-2 both standardised around 2000; ISA extensions for mainstream CPUs introduced in 2010-2017). From the software PoV SHA-3 would be a rather large regression in performance with a "maybe it's fast by 2030 if Intel is really nice" attached. BLAKE2 on the other hand is an improvement in performance and offers a function that is more modern overall. (E.g. not length-extensible thus low-overhead keyed hash usage, flexible output sizes, tree hashing built-in)