There's really not any true or false answer here.
For instance, Joe Lewis only kicked two things, people and heavy bags, never air.
Bill Wallace only kicked two things, people and air, never heavy bags.
Both had remarkable skill and great careers.
As for Shotokan, I can only speak of the East Coast. Shotokan fighters back there in the seventies, eighties nineties and two thousands - were just plain nasty to fight. I always used to describe fighting them as - "they will punch a whole right through your f'n body, just to give the finger to the guy behind you."
As for Goju, I originally trained Greek Gojo Ryu. It was a hard fighting school. They kicked bags hard, but I wasn't there long enough to know how often.
Personally, my dojo had ten to twenty heavy bags - depending on how often we broke them. Even had a couple on elevator cable, with rollers atop the bag, that went between the I-beams. That way you could drive them back with hard combos.
I loved bag work. I became a wholesaler so I could get them fairly inexpensive. I preferred TufWare leather bags. Don't know if they're still quality or not, haven't bought one in quite a while.
Neither one of those guys did Shotokan or Goju Ryu