Personally, I think if you shrunk someone like LeBron down to 6’0” they’d still make an impact on the game where on the other hand if you shrunk someone like Giannis down to 6’0” he probably wouldn’t be in the league. Is there anyone you think could still be effective in the league at a shrunken height, whether it be from 6’11” -> 6’6” or 6’6” -> 6’0”?
Jokic would be playable I think down to 6’4". I couldn’t tell you what his mobility would be like, because I’m sure his height affects that. But supposing he didn’t change that much in his speed or physicality, he could still be an effective player at multiple positions, though i think if he were less than 6’4" he’d need better mobility and/or physicality.