I've both hit and got hit by Chronos as MaxX and I agree with many here that the window for Chronos to have a real impact is very slim. Even in cases where the Chronos hit 2/3 of the deck many times it has not had a big impact. You need to hit so much of the right stuff and in general MaxX runs multiples of most important cards.
The Keyhole-Eater version runs 3s and if you manage to hit a big chunk of the deck it normally is late enough that it doesn't matter.
Reg-versions have multiples too and you are happy if you clear out one breaker type, but they still have parasites to clear out that specific type, so you also need to hit all the parasites.
On top of this you need to be able to actually score the Project at that exact moment, which is not trivial, nor reliable even if you slot 3 of them. Sure, you can run a 1of to round out your agendas and be happy when it does pay for its slot, but that seems not very often.
Attrition PE, however, should still like Chronos, but that is more about hitting any cards than hitting specific cards
Anecdote: Before my first SC this season, just after O&C came out I tested my HB:ETF against a bunch of MaxX on OCTGn and ended up not running Chronos due to it being too lackluster on a whole bunch of games. I think my deck was better off from running 2 Gila instead and won the SC.