I suggest you treat the breathless "MaxTech" YouTube videos and the folks posting them with a big grain of salt. Random IO is vastly more important than maximum bandwidth (which is the only thing that BlackMagic app they use reports on), and at that:
1. Newer machines tend to be a bit faster than the previous M1 machines
2. The entire M2 lineup is pretty close when compared amongst themselves in performance.
For things highly IO driven, like compiling (
https://github.com/devMEremenko/XcodeBenchmark) we see essentially zero performance difference between 256GB ('only' 1500MB/s) and 512GB ('only' 3000MB/s) SSDs. You can look yourself - jump down on the list (at that URL) to the comparison of Mac Mini M2 8/256 vs. Mac Mini M2 16/512. Under 1% performance difference for _compiling_, which is part and parcel of high disk IO. Also note that the M2 models wipe the floors of the M1 models of similar core characteristics.
So - take all of YouTube with a big, big grain of salt. Maximum IO is just one of many attributes of an SSD, and random IO, in normal and the vast majority of not-normal use, is vastly more important.
Also realize YouTube publishers are rewarded for views (clickbait), and saying "Well, the SSD is about the same as the last generation" won't generate near the clicks.