The problem with this argument is that it is very simplistic.

And a very simple way of de-legitimising any anti-establishment position, and protecting the status quo.

We can look at independence movements in Europe, Brexit, Trump, republicanism in the UK, any sort of heterodox economic or foreign policy.

Even if you disagree with these positions, it is helpful to you to steelman your position and your arguments. And just dismissing them as Putin's work drops you into a trap. It's arguably one reason why Trump got re-elected. People spent his entire first term assuming he'd be exposed in some complicated Russian plot and put in jail; rather than thinking hard about why he got elected in the first place. Same thing happened to some degree with the Brexit vote.