You are right in the sense that simply telling people "be vulnerable" is likely fix all issues on it's own. In general I however think it's a mistake to think in terms of mode. It's possible to put on an act in a bar that makes a guy "alpha". In a deep relationship where both parties are open it's not possible to put an act anymore and the core shines through.

A guy who's generally driven in life will be more attractive than one that isn't. A guy who also puts value on keeping strong relationships with his male friends and who knows what he's doing with his life will be more attractive than a guy who's only priority is his girlfriend. Using different tactics of interacting with the girlfriend doesn't change something about the core.

Elon Musk hooked up with an attractive actress in late 2008 while he both Tesla and SpaceX was at the brink of bankrupcy and he was loaning money for rent. At time where he was sad. He didn't do any game on the super model but told her about his emotional troubles and the sadness he feels about the state of Tesla + SpaceX. That's likely very different behavior then what the actress is used to from most guys.

I also think that's not repeatable by in the same way by a person who doesn't actually have the drive that Musk has by going to a seminar to learn how to interact with woman like Elon Musk interacts with woman. On the other hand the promise that PUA marketing sells is that you can become successful with woman mainly by focusing on becoming successful with woman.