Orlando and LA Shaq would terrorize this league. He was definitely mobile enough to cover on switches well enough to not kill his team. Meanwhile, on the other end he'd be fouling out these finesse bigs, or forcing teams to play a 2nd big to cover Shaq for stretches of the game.
People talk about spacing and shooting threes, but a guy that can bulldoze his way to the basket every time is still more efficient than anything else. Wings like Giannis or LeBron still do it, but there aren't really any bigs that can. Prime Shaq would average 35 ppg on 60% shooting easily. Surround him with three-point shooters and slashers and he'd average 5 assists too. Shaq was a very good passer out of the post. Shaq was just a very unique and special player that would be even more unique an unguardable today. Too big, too strong, too nimble, too skilled.