While simultaneously encouraging teenagers to be sexually active, giving them free contraception and ways to get abortions without even telling their parents. And sexualising people at younger and younger ages through sex ed in schools and the whole trans indoctrination agenda.
Don't get distracted by legal marriage ages though, what is relevant is the age of consent. Basically, the sensible minimum age for both sex and marriage for most people is probably somewhere in the 16-18 bracket. A few decades ago most governments had minimum ages of consent for both sex and marriage somewhere in that area. But now, Satan's governments are disconnecting sex from marriage by forcing legal marriage registration later while simultaneously encouraging sex earlier even where it remains technically illegal.
But despite all this confusion, they are not messing much with the age of consent for sexual intercourse. That seems to be staying around the same relatively sensible middle-ground age it always has been, in most jurisdictions. And for our purposes it's the only law that matters - you can't register polygamous marriages anyway so "marriage ages" are irrelevant, and I'd suggest that people getting their first marriage also think hard about whether to register it with the government (in hindsight I wish we did not register our own).
So forget the legal "marriage age". What is the legal age of consent for sexual intercourse in your jurisdiction? That becomes the practical legal minimum age to get together in a way which we'd call "marriage" and which the State will consider a "domestic partnership" or whatever since it's not registered. Go below that age and you'll go to jail and be branded for life as a child abuser. Usually deservedly (exceptions being foolish teenage lovers jumping the gun, who pretty much everyone agrees don't really deserve jail time).