I'd say among my generation (millennials), a big reason is that most who have the financial/demographic profile to be ideal candidates for golf live in or very near to very urban large cities, and there just aren't golf courses anywhere nearby. Even if I wanted to play golf, it'd be a lot of work just to get to a golf course even once a week. Also, as much as it is saddening to say this, a lot of us have jobs where even on weekends we can't be certain a week in advance that we can block off the 5-6 hours it takes to make a golf tee time, play 18 holes, and get back, shower, etc.
If these factors seem trivial to you boomers, now you know how good you had it! Golf is a luxury sport for reasons beyond just the greens fees or membership dues.
If these factors seem trivial to you boomers, now you know how good you had it! Golf is a luxury sport for reasons beyond just the greens fees or membership dues.