If not, is there something about OCaml that makes this strategy more suitable than it is for other languages?
If not, is this a case of this being the best strategy they have the resources to implement, rather than the best possible strategy?
I'm pretty sure that would have not performed well without the aggressive prediction logic in modern processors.
Java 1's object accesses always read through an indirect pointer, but that went away in the name of performance, either when Hotspot was introduced, or on the next round of GC impromevents.
Indirect pointers or Brooks pointers has it is called were used in Shenandoah v1 to allow an application thread that perform a read to not move the object during the evacuation phase. This strategy has been removed in Shenandoah v2 to have a better throughput so now both read and write by the application move the object during the evacuation phase.
ZGC has never used Brooks pointers.