Think that volume and intensity have an inverse relationship. Meaning that the more intense (or heavier) you go, the less volume (sets and reps) you’ll have.
So as the progression goes, 5×5 is more volume so the weight used even at the same RPEs will be lighter. Drop to a 4×4 and the weight will go up. An RPE 7 for 5 reps means 3-4 reps left in the tank. An RPE 7 at 4 reps will be about 3 reps left in the tank. So that should be a higher number.
Now when you come back to beat that weight later, there’s the ramping up. It should (although some days are better than others) be more than the first time you were to do that same rep range at even the same RPE. So when you come back to doing the 4s again, even at the same RPE you should be stronger and pushing more weight. Go for a small jump over the previous attempts. Keep it within the RPE.