A political tactic for introducing strategic focus into a resistant leadership team: frame the first attempt at focus as a low-risk, reversible test rather than a permanent commitment, and let leadership itself pick the area to focus on.
Having leadership choose the focus area removes one source of resistance — instead of leadership needing to take a "leap of faith" on both the idea of focus itself and the specific area chosen, they only take one leap (accepting that focus, applied to something they picked, is worth trying). This lowers the political cost of the first attempt at explicit strategic choice-making enough to get buy-in.
See concurrent-strategic-bets-cap for how many such focus areas an org can sustain at once, and strategy-continuous-feedback-loop for how the test result feeds back into the next round.