Sorry, teams can't be only devs. That's IT or something, and implies that tech isn't the business.

Team has to include 'the business', as in, voice of customer, features lens, in those tradeoff prioritizations along with what do we engineer, and what's the truth of where we are on the field, for delivering what satisfies the customer and our constraints. // Hat tip Rands in Repose.

As for "Ultimately it's not about trust, it's about accountability and predictability" that's precisely the characterization I reject. Accountability means you earn your keep by being effective. Predictability, well, milestones come and go, the software gets used forever. That's the predictability needed, which goes right back to effectiveness. You won't magic either of those in a Jira.