I wasted a year trying to figure out if I should transfer teams or just quit. In retrospect the answer was obvious, I just didn't have the framework to see it.
Here's the test I wish I'd run earlier:
Ask people on other teams. Not 'is my manager bad' (they won't answer that). Ask: 'How are things going for you here lately? Do you feel like there's a clear path at this company?' If people on other teams are also vague and frustrated, you have a company problem.
Look at attrition patterns. If only your team is churning, it's the manager. If people are leaving across orgs at a similar rate, it's structural. LinkedIn stalking is useful here. Three people from your team left in six months? One data point. Three teams all lost senior people in the same window? That's a company thing.
Offer timeline and internal mobility. At a healthy company with a bad manager, you should be able to transfer and reset. I asked my skip about internal mobility and got a bunch of vague hedging about headcount and 'timing.' That was the real answer.
Calibrate whether your compensation is tied to your manager's perception of you. At some companies your skip-level or HR drives comp fairness; at others your direct manager basically runs the show. If your manager controls your level ceiling and your raise, a bad manager is a company problem by proxy.
In my case: my manager was genuinely bad (conflict-avoidant, played favorites, took credit for roadmap work he didn't do). But the company let that continue for years with no accountability because there was no real upward feedback mechanism. That's a company problem.
I transferred anyway, things improved for about four months, then the exact same patterns showed up with my new manager because the culture selected for that type. Left. Should have left sooner.
The tell for me: when your manager's behavior is well-known and nobody above them does anything, the company is choosing that manager. Keep that in mind.