David P wrote

Neuroscientists now claim that the human
brain is not fully developed until age 25-30.

And its obvious that that never happens with some.

We should therefore raise the voting age to that level.

Nope.

Military service is different: obedience is valued over thoughtfulness.

That isnt the reason that the military has always used young kids.

They really do believe that nothing can kill them.

With elections, the reverse, thoughtfulness rather
than obedience, should yield better outcomes.

That would only be true if there is much to
think about and the facts to do that about.

No real evidence of that with politics,
particularly with complex issues like
brexit or socialism or the welfare state.

Politics has always been much more
about gut feelings and charisma etc.