To me popularity depends on application Most common. Chevy 350 for sure. Simple/poor man's hot rod reliable motor.

Sand cars... LS (all generations), subaru turbo motors (my choice),

Boats... BBC, 10 yrs ago sbc, 20 and 30 yrs ago 460 ' s

Ur buddy is not wrong for wanting to go hemi. It's just not a go to motor in the sand car industry but neither was the Northstar v8 but that proved to be the go to motor for many yes before the LS stuff became popular and affordable.