Contrary to common culture, if memory strain is an issue with GC, it is even worse with algorithms that cannot cope with fragmentation, or have to keep going down into the OS for memory management.

Optimizations to avoid fragmentation, locking contention or stop the world domino effect in reference counting algorithms, eventually end up being a poor implementation of a proper GC.

Finally, just because a language has a GC, doesn't mean it also doesn't offer language features to do manually memory management and reference counting if one feels like it.

While Java failed to build up on the learnings from Eiffel, Oberon, Modula-3, there are others that did, like D, Nim, C#.

Not all GCs are born alike.