Perhaps we were ready for Doklam but no so much for Galwan, we came out of Doklam with flying colors as if we were expecting it. Deployment was swift and matched chinese speed on the other hand during Galwan we were caught off guard we didn't start proper Deployment until months into the event.
Perhaps we did not expect them to show up in Aksai Chin?
The aggressor always has the advantage of surprise. During Doklam, we were the first movers, and during Galwan, Chinese.
Also to note, some reports say China was preparing for the 2020 conflict for since last 3 years, which means since Doklam's defeat. They had infinite time to build barracks, gather high-altitude equipment, plan strategy, and train troops.
Compared to that, our response was in haste, and we took 3 months (June - Aug) to get ready to formulate a response. Not too bad, but it could have been better.
Wasting precious flat lands for muh phool Patti.
Nah man, it is better than a barren, cold desert.