Is "Heavy Slam" better than "Body Slam" for Defense?

No STAB on heavy slam so I don't think it's better.

Body Slam is better, and Heavy Slam is just like Earthquake.

Body slam is better.

Its 50 damage, a 3 bar charge move and it hits fast. Same damage as a single hyperbeam

I have a 96% stat/IV Snorlax with Zen Headbutt and Heavy Slam. I want to say that this is his new best gym defender moveset seeing as Snorlax can no longer spawn Body Slam anymore. A lot of sources including this one place Zen Headbutt and Hyper Beam as his best gym defender moveset but Hyper Beam is so easy to dodge. I wish that Snorlax could still spawn Body Slam but at least Heavy Slam is super effective against Rock types, including Tyranitar and Rhydon, which people are now using to counter Snorlax, while Body Slam isn't/wasn't, same as Hyper Beam. Earthquake is also super effective against Rock types but Snorlax can use Heavy Slam more frequently.