Briar supply is good. There has been a shift away from the big factories requiring 400,000 blocks of no particular character towards artisans and smaller shops needing better and more specific types of pieces. But briar is fairly fast growing as a plant, and there's tons and tons of it around. The cutters I've chatted with operate as forestry managers, they take the trees that are ready, leave the ones that aren't. But the idea of "running out" is preposterous - there's far less overall demand for briar today than there was 40 (or whatever) years ago. The demand for super-briar is of course as high as it's ever been - every hobbyist is emailing the cutters and vendors looking for a whopping 3 top-grade uber-blocks at this point, and there's thousands of those guys now where there just wasn't before.
But what is available now is absolutely as good (arguable better) then what has ever been available - standards are high, information and product is widely available. It's all good. I can get briar from various vendors that would put a DR or an Autograph to shame. I have access to whatever cuts I want, whatever sizes, and I can choose Greece, Algeria, or any number of Italian vendors, let alone Turkey, Corsica, Morocco, whatever.
But what is available now is absolutely as good (arguable better) then what has ever been available - standards are high, information and product is widely available. It's all good. I can get briar from various vendors that would put a DR or an Autograph to shame. I have access to whatever cuts I want, whatever sizes, and I can choose Greece, Algeria, or any number of Italian vendors, let alone Turkey, Corsica, Morocco, whatever.