Offered a promotion that pays less per hour than my current role

What we told them

Separate the two questions: is the trade worth it now, and does refusing close the door? On the money it is a pay cut per hour and you already know that. The real question is what the role buys you that the money does not — scope, a reference, a skill you cannot get elsewhere. Say yes if you can name that thing specifically. If you cannot, decline in a way that keeps the door open: ask what the next opportunity looks like and when. Declining once rarely ends progression; declining without offering an alternative sometimes does.