I was receiving the 40% off offers weekly until one week when I didn't use up all three of them. Memorial Day week I didn't get any at all. Week after that I got three of the 20% off. Used one. Got three of the 40% off the next week. And the week after that (this week) three 20% again.
They're definitely being stingy. My brother has a corporate card linked to his account and he stopped getting the Uber Eats offers altogether a few weeks ago. He's going to end his Uber One membership at the end of the month because of it.