Excellent points ... there are many coaches who either don't understand the system or will say anything to get talent.
There are also many parents who do not want to believe their daughter is actually a D2 player, and as many who feel that if the club team doesn't win a seventh grade tournament in Modesto then the coach is terrible and it's time to change teams.
The issue from a coaching standpoint is often that developing players (improving their three-point shooting, say) means losing some games, and too many parents measure a club's success by games won rather than player development.
And of course the player wants to a) play with her friends or b) play on a team with good players or c) play on a team with a good social media presence, or all three -- and none of those will necessarily help her reach her potential.
I don't think parents would have an issue with being told that their daughter is a D2 player if they were given better information. It's pushed too hard that if you're not a D1 player, you're a lesser player. Even your statement could be read that way. In actuality, according to a recent
NCAA study, it's just as hard to become a D2 player as it is to become a D1 player, and D3 isn't much easier. But because of the "D1 or bust" mentality that is pushed by a decent amount of club coaches and recruiting gurus, parents turn up their nose at the thought of anything other than D1 offers.
Parents measure a club's success based on what they are told by the director upon joining, especially at the youth level. The first club my daughter was a part of preached development and getting her ready for high school and beyond. In actuality, there was no development (I don't count warm-up drills as development), so all there was to judge the club on was performance in games and the skill of the coaches in those games. That tended to be the theme for every club that tried to get us to switch to them: the director and coaches preached development, but the parents said otherwise.
As far as your example of the parent who is pissed that you lost a 7th grade tournament in Modesto, there are a myriad of reasons why losing what a coach considers a minor tournament that may push a parent into wanting to leave. Did a player get to start after missing practice all week, even though there's a "no practice, no starting" rule for the club? Has the parent been with the club for a long time and seen no growth in their child, and a loss while seeing their kid barely play again is the last straw? I agree that there are situations where parents overreact, but there are some where the reaction is justifiable.
Even if a player ignores all of those reasons you mentioned, they may still never reach their potential. It just happens.