Well, one can always start by learning the language, reading books, watching movies and listening to songs of said culture, studying the history, crafts, and traditions, and going there for multiple years on their 2-week vacations, not just as an one-off of off to the next destination.
And if they're really serious, then proving it by putting skin in the game, not just a 2 week retreat: moving there, for example.
Even the latter, hardcore thing, is not some elite suggestion. Millions have done it, including richer, middle class, and poor people, that were fascinated with another country / culture / lifestyle.