I just had a very pleasant campaign where I tried to collect as much artifacts as possible but now they are practically worthless to me.
... you do realize this new version is not save-compatible with previous versions, right?
And even if it were, nobody's stopping you from finishing up a campaign on an older version. It just means you won't be able to play Deus Ex Artifactae going forward, similar to how Deus Ex Sanguinas strategies were eliminated in earlier versions of HIP. Just add it to the list of HIP's anti-snowballing efforts, alongside Imperial Decay, dynamic levies, CB restrictions, retraction of Eldership succession from unreformed Baltic pagans, the aforementioned bloodline nerfs (+ the fact that historical bloodlines deactivate if you don't belong to a certain culture), the severe nerfs to troop stat boosts from religions, the trade post limit changes for MRs... you get the idea.
As for the Supernatural Events thing, I frankly do not believe it would be worth the amount of time and work needed to have unrealistic-boosting and realistic-boosting versions of basically every single artifact. The Holy Grail is easy because the artifact can only be gotten by a single event (so you just need to put a single rule-check into a single event and you're good), it does not interact with other events once it spawns (like the way e.g. the Reichskrone and the Imperial Diadem do), and the supernatural effect itself is about as harmless as you can get from a snowballing perspective (bonus Health just makes you current character not die as early from a natural death, but it doesn't prevent the usual age-related penalties from taking hold even if you do live longer, and sometimes you don't really want to live as long with your character as you'd end up living). If you feel like you have the time to spare though and this issue is important to you, feel free to make a submod that does the whole artifact-boosts-types-gated-by-rule thing you're talking about.
- 1