Depends what’s meant by tactician.
Koeman played a lot of formations, Martinez did work on positional aspects to reveice the ball from the keeper (Best role tactic was the Lukaku on the right wing vs Arsenal but that only worked once), Moyes use of 4-5-1 made us better than many people’s expectations.
With all the videos available to everyone of how each team plays I’d assume that most of the “tactical” side of things is so small these days that it’s quite hard to notice most of the tweaks that could be considered tactics.
Biggest thing for a coach is getting them to do, what you want them to do.
Koeman and Martinez had big issues here, whether that was coaching ability or communication issues only those close to the game will really know.
You’d assume that Moyes was ok at this (whatever you think of what that was), as most teams were identifiable.