[Some speculate that Lukashenko would like to be the next Czar of a re-unified Russian Empire, and that he could be an acceptable figurehead to the security services elites who run Russia.]
Not so much that Putin is a figurehead, as that he can’t continue long term as the public face, if they want to get sanctions lifted. Russia can’t be rehabilitated if he is.
No one else can take the blame, to get Russia rehabilitated.
He might also have one of the many rumored health issues, and jockeying could be going on.