Singles vs multi-rep sets with same weight

This strikes me as one of those questions that has likely been asked and answered but I’ve searched and I don’t see it.

I’ve been trying to find out the purpose of uninterrupted reps, as opposed to lots of singles (without changing intensity). For strength gains, are the later reps in a set more or less effective at improving strength? I’m focused primarily on strength, rather than power or hypertrophy.

Example: Let’s say my squat 1RM is 400. My planned workout for the morning includes squatting 3 sets of 5 at 80% of 1RM. So, the plan is: 3 sets of 5 reps at 320 pounds with 4-5 min rest between sets.

But, I decide to do something different today: 15 singles. I’m not going to do more weight. I’m not changing any other variables in terms of tempo, ROM, etc. I’m just going to rack the bar and rest a minute or two after every rep, instead of racking it and resting after every fifth rep.

What difference would we expect this to make? Am I applying a different type of stress that will drive a different physiological or metabolic adaptation?

My guess is that, for the 15 singles, force production and bar speed will be more consistent for each rep, because I will be relatively well rested for each rep - no intraset fatigue. In a set of five, do we drive a different adaptation with the first rep than we do with the fifth rep? If so, what is it?

To be clear, I’m not asking about the difference between 3 sets of 5 at 80% of 1RM vs 15 singles at 95%. I’m asking about the difference between: 3 x 5 @ 80% 1RM and 15 x 1 @ 80% 1RM

I’ve seen discussions about, for example, 3x5 vs 5x3. But the discussions always involve different weights (3x5 @ 80% vs 5x3 @85-90%), and focus on whether or how to increase intensity without lowering volume. I’m not asking about increasing intensity. I’m just curious what we get for uninterrupted reps vs singles (aside from maybe saving time).