I don’t necessarily think Putin did this.
He did not - in the sense of pulling the trigger; any more than Hitler actually shoving anyone into an oven or gas chamber.
He did, however, turn this area into a war zone. This lies on his doorstep. He aided, abetted, egged-on and encouraged a civil war upon the removal of a thieving dictator.
This is solidly his mess. His people shot down this jet. Putin's boys.
Or as they say in CEE, Putin's circus, Putin's monkeys.