Top 10 lies society tells women:

1.  You can have it all -- career, independence, husband, and children.  Everything at once.
2.  You're beautiful at any size -- your weight and health don't matter.  You're still beautiful no matter what health conditions you have or how overweight you are.
3.  You can date around, just like men -- your "romantic" past doesn't matter and you can have "free love" the same as men, with no consequences.
4.  Mr Right is out there, waiting -- you don't have to be intentional about marriage, you don't have to be serious about learning homemaking skills.  It'll just happen.
5.  Men want a woman who is a "challenge" -- you should be a "boss babe" who challenges their husband and brings complexity to the home.
6.  Your peak will be your 30s and 40s -- your best days are not your 20s (when you're most fertile) and your looks keep getting better, into your 40s.
7.  If the guy isn't interested, he's the problem -- Guys are the reason you're not married, not you.  Everything you're doing is fine; no need to change.
8.  Your career should be your priority -- Your job should always take priority to men.  Your career is your safety net.  Relationships will always be there.
9.  You can "manifest" success and happiness -- Being positive and believing in your destiny (and/or using new-age energy or crystals) can make your dreams come true.
10.  You can have kids at any age -- You can control time, freeze your eggs, and get married when "the right guy comes along".

If you believe any of the above, be warned, you're being sucked into the feminist vortex.

I would say a women in her teenage years are more fertile than her 20s.

Fertility + maturity = one's peak, for women.  This is typically in the early 20s.  Teenagers aren't mature enough. 

Are you sure that present day women are mature enough in their early 20s?

I wouldn't say so.

Being older doesn't automatically translate into being more mature. A women might mature if she learns from her mistakes but many men aren't interested in a women who has "mistakes".

A good upbringing makes a person mature. Most modern women aren't mature regardless of their age, though this is dependant on the subject matter. As a women might appear mature at first in some areas but as soon as mention something that goes against the grain they reveal themselves.