Macbook "press and hold power button for 10 seconds"?

In the official Apple support guide to reset the SMC of a Mac with the T2 chip, it says:

Before resetting the SMC, try these steps:

1. Shut down your Mac.
2. Press and hold the power button for 10 seconds, then release the button.
3. Wait a few seconds, then press the power button to turn on your Mac.

What does step 2 do?

Solution 1:

Step 2 simply tells the hardware that you want the SMC chip cache to be reset. It in itself likely doesn't do anything other than differentiate to the hardware your intention. This way, there is no confusion between a 'normal' power button press and one that requests resets.

Solution 2:

Step 2 is a forced shutdown of the machine. Internally it likely causes the system to clean out a few caches, run some verification checks, and the like, because the system assumes a forced shutdown means the user experienced a problem. In effect, these three steps ask you to do a normal shutdown (so you don't lose open data), start the machine and immediately perform a forced shutdown, and then restart it to see if that fixed the problem.

It's a bit more high-tech than slapping the side of the computer to see if that sorts it out, but kind of in the same spirit.