I would say 15. Kids today grow up fast and at 15 they are old enough to have sex. Any younger is pushing the bounderies a bit.
I think it is unlikely to ever be reduced below 16, as too many people would complain. Probably people who should be minding their own business and have empty lives or too much time on their hands or something. Complain, complain, complain about what innocent people wish to get up to in their own private lives. Perhaps thats what big brother theory is all about? Looking nosily into peoples lives and actually making problems instead of solving problems.
Many 15 year olds have sex with 17/18 year olds anyhow. It is sad when they end up being charged over it. But the law is there to protect, so they say
Protect from what exactly?
A political decision made by politicians who probably broke that law in the first place - in secret. That sounds about right