Is it implemented, planned or does not align with project philosophy?

To make it compatible a compat mod required, yes you're right. I understand, it's not designed for tech mods ecosystem, it's more for datapack based projects.

Hello,

Firstly, datapacks are vanilla features, they're not the same as mods, they do not contain any Java code so they can't communicate with mods by any way (unless someone make a mod for it, which isn't the case).

Secondly, as a datapacker, I only provide compatibility experience with other datapacks. Even if I wanted, the overhead of making special compatibility with mods is unreachable and pretty useless as 99% of people playing with datapacks don't use any mods, as well as the other way round (people using mods don't use datapacks)