Google is further signaling the decay of attribution modeling with the announcement:
First click, linear, time decay and position-based attribution models are going away
None of these were great. Data-driven replaced position-based and GA4’s shift to user (and event)-based measurement over session-based made first click redundant.
But I think this is an admission from Big G that (aside from last click) accurate attribution is hard to do in a post-cookie world, so it’s all about data modeling now.