The Commmission report linked above mentions that USAF pilots are concerned about the increasing use of simulation but shys away from making any finding on the proportion. Indeed the report reads as if the Commission members have supped lightly from the Kool-aid. They don't pull any punches on experience levels, though:
The Commission learned of students who completed a rushed initial training program, who were pushed through their follow-on training by less-experienced instructors, and then became instructors and leaders themselves. They are at higher risk of making costly mistakes and lack the experience to train the next generation. Without action, military aviators will not be exposed to what “right” looks like. Inexperience will become institutionalized and jeopardize the safety of a future generation of aviators.
Yup.