Yeah, it doesn't seem terribly fair. I've had ideation since I was 10. I'm not so convinced my thinking was so different aged 18, 20, 25, 30 as it is now- in my 40's.
Things can change- of course. They can get better. They can also stay the same or get worse! That's true of any age though. Plus- just because it works out for one person, doesn't mean it will for another and vice versa. The most important thing though I feel is the want to try. If that's gone- these people should at least concede that they are forcing people to stay against their own will- which to my mind is going to be less effective than really listening to what that person wants and more importantly- why!
They are going to have reasons they want to end it! At least go about it practically and find out what those reasons are... Maybe there are things they haven't considered and maybe they will be willing to try them. That to my mind sounds reasonable to just suggest them. We can all become kind of blinkered and pessimistic in life.
Still- they may just as well have thought of those things themselves, tried them or simply thought- they don't want to try them! So again- if that's the case- pro-lifers out there- admit to yourselves what you're doing! You're forcing an adult to do something they've chosen not to do because you think you know them better than they know themselves. Maybe you'll be right in the long run and I guess that's what this sentiment is based on- if we can 'save' just one person...You have to wonder just how realistic it is though. Can someone who doesn't want to be saved be saved?
In any respect- belittling them with the- 'You're too young to know shit' tactic I'd say wasn't the way to go! Nothing like belittling and insulting the person you are claiming to want to understand and help.
Of course- there is the argument that our brains haven't fully developed until we are 24-25 or whatever. Even still- remember you at that age. At that age, I was living fairly independently and doing my degree. I wouldn't appeciate some priggish adult telling me my brain was a tadpole effectively. Even if it is true- preaching to people like that is going to rub them up the wrong way!