apart from Bay Trail I don't think Celerons were ever THAT bad,
perhaps the original l2-less p2, or Northwood, but other than that, I can think of a lot of good or even great Celerons (300A, Tualatin, Celeron D, Core 2 Celerons like e3200, sandy bridge+ Celerons), I think they always delivered good perf/price, until sandy bridge also good OC potential, obviously once Pentium was moved to the low end, Celerons was even further down, but it's not really a significant difference,
I guess Intel sees some advantage for keeping it, perhaps some expect their cheap PC to have a Celeron, maybe they will be OK with that, or will want to pay a little extra to avoid it lol
g3900 should be pretty good,