So I've seen that post on gitp before. My issue with it is that the numbers are wrong.
The easy place to see this is the spells, D&D beyond has an easily searchable by save required spell list. That I have checked against the paper books. The results from that are as follows;
Str
17
Dex 58
Con
36
Int
3
Wis
40
Cha
12
Source
The counts he got wrong are bolded. The only one he got correct is Dex saves. I don't have a searchable version of the MM/volo's or an infinite amount of time so I don't have those numbers. However, the fact that he has 5/6 of the counts for spells incorrect brings the accuracy of his counts in other areas definitely into question.
For bonus I'll also do class features
Str
5
Dex
3
Str or dex 1 (nature's wrath let's the target choose, this may be where he got 6 and 4)
Con 5
Int 1
Wis
16
Cha
1
the target's spellcasting modifier 1 (spell thief)
Even discounting the str and dex assuming it was nature's wrath added to both he has 2 more incorrect counts.
I didn't count anything on the wild magic surge table because of the inherent randomness involved.
I really can't trust a 58.3% accuracy for the massive job of digging through the MM/volo's.