There are a few papers about Haskell's GC by Simon Marlow where this is discussed. The absence of mutable references is a big win for writing a concurrent collector.
My point is that writing a GC for Java has in fact proved very difficult. It took Sun and Oracle many man years and different GC designs to get where they are today. So it seems Java also needs a "good" concurrent GC. With both functional and OOP languages generating a lot of garbage and sharing language features, I don't see a big difference in requirements in practice. And sure enough, Clojure/Scala seems to work well using the JVM GC and F# seems to work well with the .NET GC too.
I think the burden of proof rests with you and your statement that the concurrent GC situation is somehow more challenging for an FP language.
> I only accept CS papers about it
Me too