Answer to "iPad Pro 12.9 touchscreen is unresponsive from time to time"Okey, seems on my end it was a hardware issue (I tried hardware reset, disabling iPad features, removing apps - nothing helped. It looked like it helped but then touch delays were getting back). Apple replaced the iPad and all my problems went away.
Answer to "iPad Pro 12.9 touchscreen is unresponsive from time to time"I tried all solutions in this thread - nothing helped. After that I realized on my side the problem is connected to the Smart Cover. When I connect Smart Cover I have all sorts of problems with unresponsive touch. When I disconnect Smart Cover it works just fine!