That makes sense, but it is still risky when your country now has access to global news. Russians overthrew their government twice in the last century. They could do it again. Why not target the biggest threats secretly (more secretly than a suspicious shooting and poisoning)?
Could be ego.
Maybe he's gotten to the point that he's so full of his own success that he doesn't think he can be overthrown and is choosing to intimidate more openly while also flaunting his power and control.
What method do you propose? Arkancide? You sound like an apologist for Putin, to me.