It's tough to talk about briar as a medium without sounding mystical or even just a little stupid. I've had something like 8 new Castellos I guess, and most of them smoked unproblematically from the get go, but none of them dazzled me either. And a couple tasted really strange, honestly, a sort of lakeland flavor, like rosewater burbled up in the first bowls in a couple. That's not a briar flavor, that's something splashed into or soaked up by the pipe after manufacture. (Possibly sitting next to a bag of Condor in a display window? Possibly a little je ne sais quoi at the factory....)
I think in general a "bare bowl" pipe (no pre-carb coating) will have a slightly muting effect on any tobacco, the edges will be taken off the flavor as the briar is absorbing a little, and adding a little - a slightly corky flavor is pretty common in Italian wood for example (as opposed to a slightly cinnamon-like note in Algerian, and slightly earthy flavors in greek wood). So I don't think it's uncommon for a new Castello or Ardor, Don Carlos, Radice etc, any of the "bare wood" brands, to be a little shy at first. But they build into tremendous pipes with just a little use.
Castello has good quality wood, and with some age on it, it breaks in pretty fast and without much fuss. I see them as pretty linear, good smokers that get great with a few uses.
But if you have never had a bare-wood bowl before, I can see it being a slightly off putting experience. I look forward to it myself, part of my aquaintance with the pipe, part of the relationship I am building, learning what the pipe tastes like, how open the draw is, what it seems to be best at smoking, what I'm going to use it for. This, to me, is part of the beauty of pipe smoking. There is an interplay between pipe and pipe smoker, something like a musical instrument. Guitars all have six strings but a Fender shallow-V and a Gibson neck feel totally different. And both are good.
I smoke the shit out of my Castellos, they hit a sweet spot for me of price, quality, one-of-a-kindness, and they have a playful countenance and a serious soul. Well made pipes mostly, with a little eccentricity. So don't give up on that thing, just quit expecting a miracle. The miracle may come in time, it may not. There are people who don't find value in Castellos, there are people who don't find much value in briars of any kind. So be it.