It doesn't invalidate it neither. For the record, I believe that an age of consent is necessary, and that 14 is WAAAAYYY too young for any kind of romance. HOWEVER:

The same reasons that we say it is inappropriate for a 14 year old, would also apply to a lot of 18-20 year olds out there, or 16-17 year olds, the latter being the age of consent in some states and many countries all over the world.

OBVIOUSLY and 18 year old is going to be much more mature than a 14 year old, but frankly, for many teens out there, it's not that much of a difference when they are talking to a 28-45 year old man.

What I mean to say is, if a 14 year old and an 18 year old each play against a 30 year old guy in a game of "life chess", they are both extremely likely to lose due to being too naive or inexperienced.

Heck, we have full grown adults that got taken for their life savings by predatory real estate agents and loans. We have 19 year olds that don't know their dick from a kebab, losing their limbs in wars that they don't know anything about.

The basis upon which we say 14 is too young, is the same basis upon which older people are allowed to make decisions that alter their lives just as drastically. Therefore, a fair amount of this is conditioning, that was only introduced to most of the world less than 1 lifetime ago.