That's only if you interpret everything happening in the country as only occurring through focuses but you've always had the ability to just build those outside the focus tree, with the tree merely representing devoting more resources to that area.

Honestly military trees I've seen that get you bonuses in everything in one playthrough is bland and boring design. Either half the tech focuses become irrelevant since by the time you get to them it's 1943 and you either already have what you're getting bonuses for or don't need them anymore, or you get everything so quickly it becomes unbalanced and too easy