From my limited knowledge (mostly based on jneems article series[1]), I think Pijul is more powerful, but for the same reason also considerably more difficult to understand than Git.
In particular, Pijul supports (and depends on) working with repository states that are, in Git terms, not fully resolved. In addition, those states are potentially very difficult to even represent as flat files (see e.g. [2]). Git is simpler in that it mandates that each commit represents a fully valid filesystem state.
That said, I still think Pijul might have a place, if it turns out that it supports superior workflows that aren't possible in Git. But the "VCS elitism" would probably become worse than it is today.
I really like the way Pijul "thinks". Unfortunately, I can't see myself using it (or Fossil, for that matter) for anything except toy code, because I have contract requirements to store everything in GitLab.
[1]: https://pijul.org