If alcohol consumption fixed declining birth rates, Japan wouldn’t have an aging population and Russia wouldn’t have been facing a demographic collapse even before the Ukraine invasion.
This isn’t about boosting sex, it’s about being a conservative policy counterweight to opening the door to legalizing medicines derived from cannabis.
My guess is that it’s a result of an internal NJP compromise between center right and hard right factions: only agreeing to allow liberalized medical cannabis policy, if the law also increased the scope of, and penalties for, recreational uses.
But that’s just my assumption based on my limited understanding of Japan’s post-war uniparty government.