Right, a bad phrasing from my part; I didn't actually mean the distribution, but more like... the bang for the buck. Why would you use slow generator as a default, if you don't even get good distribution?
You get a good distribution in 99.99% of the cases. There is no perfect rng. I am sure that pcg and xoroshiro also have deficiencies. The issue of good seedings is quite general.
