You're slipping back because doing the work used to be how you knew you were adding value, and you haven't replaced that signal. It's not about trust. Until you change what you measure yourself on, you'll keep pulling yourself back in to win the old game.
Stop asking how to delegate without dropping quality. If the team were below the bar you'd be hiring, not asking. The question is how you know you're useful when you're not the one shipping. Answer that and the behavior follows. Right now your scoreboard is the quality of individual deliverables. Change it to whether the team is sharper month over month. Different game, different instinct.
Here's what to do.
Pick the one deliverable type you grab most often. Write down what good looks like — output criteria, not process — and hand it over. Then go hands-off for 60 days on that category. Not 80 percent. Off.
Tell the team you're not touching it and to call you out if you drift. Pick someone to check in monthly on whether you held the line.