Some of the algorithms are built deep into the runtime. E.g. languages that rely on malloc/free allocators (which require maintaining free lists) are making a pretty significnant tradoff of wasting CPU to save on RAM as opposed to languages using moving collectors.

Free lists aren't expensive for most usage patterns. For cases where they are we've got stuff like arena allocators. Meanwhile GC is hardly cheap.

Of course memory safety has a quality all its own.