How much range and ability would you need to sing these vocal lines consistently?

tm3916

I've heard that singers sing below their max range as it would be too inconsistent to sing these notes live, for example if my top note in chest mix was a c5 i would only sing to a b4 or bb4.

If thats true then how much range does this singer have, to just be chilling around b4-e5 in a chest mix? John Farnham boggles my mind, his voice keeps me up at night, would love to hear ken do a breakdown of his voice, best male vocalist in my opinion.

https://youtu.be/3aM3BFAIdow?t=210

https://youtu.be/3aM3BFAIdow?t=267

https://youtu.be/NyfOXx-uUIk?t=152

https://youtu.be/dv54giOSRKs?t=216

Wigs

I don't know what Johnny's range is but he is extremely talented and hard working! As for max range and usability I answered a similar question here.

https://forum.kentamplinvocalacademy.com/discussion/15966/struggling-with-song#latest