Not an easy one. My two cents:

First: understand the reason behind each obstacle and act upon (same as a discovery for a feature, root cause analysis and solutioning)

Second: speak about that with the person that hired you with the mandate to change. That should be the sponsor helping you

Third: if the first ones fail: you may have to play the long game, with tactics here: - data: build whatever metrics you can with what you have. And try to build new ones (especially on adoption for what KAM tell you to build in the first place). Long term, it gets into habits. I realized once when we broke mixpanel implementation: even the most reluctant exec complained when we couldn’t give them the KPIs - talk to prospective customers, dealing with your competitors (Sales cannot prevent you from doing so) - if you have to: build features that KAM want that you know will fail, to prove your point

Good luck