Without Epic integrating it as part of the engine it can mean that even if Nvidia provides it for free that people would still have to do some work to make sure that it works correctly with the version of the engine they’re using and that it doesn’t break or have problems with other features. One of the reasons that SVOGI wasn’t kept in the engine was that they didn’t want to have to keep doing work to make sure it worked properly with each engine update. So ultimately it would be nice if it would be officially integrated, since many people don’t want to mess with coding.
I will note though, that while this is being touted as a feature of the new graphics cards that the old ones still support it, it’s just that these new ones are optimized for it.