If anything I would want to raise the voting age to 21.
If I was a leftist supporter, I would be all for it since they damn well know most uninformed teens are left leaning until they grow up.
There is a big difference between being 21 and being 18. There is a big difference between being 18 and being 16. Now there may be a variance by a percentage with different individuals. But maturity is more of a factor if not common sense knowing politics.