> Why on earth Putin & Co will try to evade taxes and hide his money?
There's plenty in Russia who believe that while his cronies live off bribes and embezzlement, Putin himself is a Platonic father of the nation. One argument you hear often is he doesn't need to steal anything because he could have everything. This has certain moralistic beauty of a man one with his country. It also provides a way for an average broke Russian to identify with the sacred figure.
Finding out he earmarked some just in case undermines that and suggests Putin himself might not be so certain in near future. And while this revelation will have no immediate social consequence and indeed will be feverishly denied by his supporters, with time it will still sink in.