One big difference Gen 5 made was that TMs had unlimited use. Which was a godsend. Meanwhile, for Gen 3 games it has also been figured out how to implement it. Pretty simple hex edit really if you know how to follow instructions.
But I've seen nothing of the sort of Gen 4 games. Naturally they aren't as easy to hack as Gen 3 games afaik. So I'd assume it won't just happen by snapping your fingers. Yet I don't see anything about it at all. Like no one is even giving it a thought to implement the unlimited use of TMs in Gen 4 games. Has nobody tried this yet or they have and given up?
From a non-hacking perspective it's such a small thing that changes a lot. So it would be great if it could be implemented in Gen 4 games too and not just Gen 3 games. Mostly because I don't really care much for the gen 3 style games.