Do you know if you marinate meat especially pork, you must use your fingers to grasp meat n knead well to soften the fibres. Chopsticks cannot knead meat well. It turns soft with the right touch. Try it.
I guessed you do not know the tricks if marinating meat n especially pork ribs. Without kneading the meat with marinade n adding in papaya enzyme, the ribs would be tough. Tricks of the trade whether in domestic or restaurant cooking.