This could age poorly still
but personally I like that Fallows wasn't sacked. He was promoted from Head of Aero in Red Bull to TD in Aston but it seems that apart from the very start that promotion did not go well, the team has been suffering from a lack of leadership, seen in differences of opinion between the track team and the factory, each wanting to do different things... Sometimes it just doesn't work out but that doesn't mean he isn't a great aero guy and could be useful to retain him. James Allison of all people was responsible for the horrendous F14T and later fired by Ferrari but that did not make him useless at all as we know.
It would have been easy for Stroll to make Fallows the scapegoat taking the entire blame for the recent failures and axe him like it is often done in football and in the most political teams of the grid. But instead Stroll chose to reinforce the technical leadership with Newey and Cardile in order to aid (and supervise) Fallows at the top of the pyramid. I think that was the correct path.