Digging for floating foundation

I'm getting ready to put in the following 8x10 shed:

https://suncast.com/tremont-storage-shed-bms8100.html

I was going to do the recommended wooden foundation they have in their documentation, and im looking at doing a floating base. I found this video when researching:

https://youtu.be/ah2-a-GADLQ?is=ISWGuLsJEhp7\_F8S

I like the process and feel it's fairly straightforward, but i see in the comments theres a few people critical that the person in the video didnt dig down before putting down the tuffblocks. Im the video they clear the grass, tamp down the soil, put gravel down then tamp down the gravel.

Is whats demonstrated in the video enough, or would it be better to dig into the soil, tamp down, fill with gravel, then tamp down?

I appreciate any pointers. I've never done anything like this so I'm a little nervous.