If you’re going to dial back, my personal preference would be to cut back on the volume, rather than the effort. Doing very hard sets will help you retain your muscle mass, and doing less of those sets will decrease your recovery demands. I would drop pretty much all exercises to 2 straight sets to failure.
You want to go balls to the walls? That’s fine. In fact, I’d rather do that than all the complicated 1-2-3-whatever reps in the tank. How can you even tell that you had a certain amount of reps left in you? That’s my main problem with anything under rpe 10, MAYBE 9.
If you go to the point where you failed midway through your attempted rep, or if you managed to complete your last rep with brain-splitting effort knowing you absolutely can’t even remotely do another one, you know you were at an rpe 10. If your last rep is incredibily hard and painful, but your form is still tight, and you’re unsure an additional rep would be safe, you’re probably at rep 9.
But below that? I know I can’t tell whether I still have 2, 3, or 4 reps in the tank. I call all those sets warm ups, or feeders (à la Meadows).
I actually have a much simpler explanation for that: I’m lazy as fuck. If I’m going to be moving any weight at all, I won’t bother doing stuff that might be in vain. If I’m bothering doing a set at all, I demand that said set will do something good to me, so it better be ball-busting: I don’t want to do any more work than what’ll get me results.