You’re conflating.

One is an individual choice and action. No one talking about age gap relationships is suggesting making them illegal. They just want them to not be normalized and for young women to be made aware of certain dynamics in many of them. It’s public messaging in much the same way as you might have public messaging on family planning.

Putting your life on the line to protest a brutal regime is an individual action and choice but ones taken as a collective, usually. Sometimes dying for a cause is worth it, a good move, and the smartest play you have. If enough women stand up and say “I’d rather die than have to live this way in this country one more day" then things change. No country can survive without women creating the next generation. Men and the elders cannot bear to watch masses of their young women happily choose death over submission to brutality. They’ll back off. Spite suicides are incredibly effective in certain circumstances. Mass lynchings don’t always have the effect you’d think to quell a rebellion. Martyrs have a tendency to give energy to revolutions.

Every lynched or executed woman in Iran becomes a martyr.

Anyway, brain development is not a good argument here. It’s apples and oranges.