I feel Jokic got calls and FTs being guarded by the Spurs frontcourt bigs whereas he wouldn’t against teams that place guards on him

Jokic got 15FTAs against the Wemby Spurs today and all of them were the correct call

The Spurs mixed having Wemby guard him 1:1 or having him as a floater/rim protector close by with another big guardians him. The Timberwolves defend Jokic similarly with Gobert and Randle.

However against OKC and Lakers, Jokic is instead defended by guards (Caruso or Smart) and doesn’t get anywhere near the the FTs and the contact is vastly different.

Is this a problem in the NBA that guards are allowed to hold and hack bigs while bigs are not allowed to do the same? If so why do you think the NBA wants this to happen?