mahemmTo me this is completely unrelated to the quality of the PRNG, because security is explicitly a non-goal of the design. A general-purpose non-cryptographically secure PRNG is evaluated primarily on speed and uniformity of output. Any other qualities can certainly be interesting, but they're orthogonal to (how I would evaluate) quality.
CSPRNGs have all of the desirable properties for the output.
All else being equal, I don't think it is possible for a trivially reversible generator to have better statistical properties than a generator whose output behaves more like a CSPRNG.
It can definitely be good enough and or faster, though.
Right, I think defaulting to a CSPRNG is a pretty sane decision, and you'd know if you had need of a non-CSPRNG RNG. But what does that say about the choice between PCG and xorshiro?
Defaulting to a CSPRNG pre-seeded with system randomness is not a bad choice per se(especially given many users don't know they need one) but current ones are much slower than the RNGs we are discussing.
If you're going to provide a non-CS one for general simulation purposes, you probably want the one that is the closest to indistinguishable from random data as you can without compromising performance, though.
Some people will have more than enough with a traditional LCG(MC isn't even using RNGs anymore) but others may be using more of the output in semantically relevant ways where it won't work.
If Xoshiro's state can be trivially recovered from a short span of the output, there is a local bias right there that PractRand lets through but that your application could accidentally uncover.
The choice is: Are the performance gains enough to justify that risk?