"Unable to 'return' humans to the Moon..."
His whole premise fails right there. NASA could return humans to the moon if they chose to do so, but they choose not to do so for a number of reasons.
1. Cost/benefit. With Apollo, the US Government poured in shiploads of money to accomplish a task; get to the moon, and the only real cost/benefit considered was "beat the Soviets there whatever it costs.". These days, NASA would have to justify sending people there again.
2. Safety. In the 1960's NASA and the Apollo astronauts were prepared to take HUGE risks to go to the Moon. They killed three astronauts trying to do this, and came perilously close to killing six more. It was a time of the Cold War; sticking it to the Soviets meant compromising safety was acceptable, beside which, "workplace safety" wasn't a term we'd ever heard of. The kinds of risks they took during the Apollo program quite simply would not be tolerated now.
3. Been there, done that. Simply going to the moon to prove we could do it is no longer an option; we've already done that. Any future Lunar missions would have to be looking at a permanent establishment of a human presence, and that is far, far harder than simply sending a few people there for a few days to pick up some rocks. It took six successful missions and the sending of an actual scientist before any real science was done. Looking back it now, I feel a pang of disappointment that with Apollo 17, they finally started making actual important discoveries at the end.....and then stopped .
4. Lost/Change of focus. After Apollo, NASA changed its focus to manned LEO and unmanned missions to planets. Manned deep space missions were put on the back burner; there wasn't enough money to keep the old equipment running (launch pads, mission control etc). All that would have to be developed again. Also, the fact is that Apollo was a "single-use-one-off" concept meant that you blasted almost 3000 tonnes of spacecraft into space, and you got less than six tines of it back