A few people report some success with tissue culture in that genus, e.g. (use Sci-Hub)
http://www.bioone.org/doi/pdf/10.25223/brad.n1.1983.a8
https://www.jstor.org/stable/42790034
A highly paywalled article seems to say this hasn't been commercially viable yet, though:
https://www.google.com/search?q=%22Inability+to+mass+produce...
Probably if demand remains high, someone will figure out a protocol and the price will come down. It would probably still take years to grow the plantlets to marketable size, though. Otherwise it looks like various nurseries are propagating them traditionally, but that will take even longer.
> While they're easily cultivated from seed and grown in nurseries both in the United States and in Asia, the large, old, wild-harvested Dudleya are considered luxury items by collectors overseas and command high prices, sources said. Imperfections inflicted by the elements are a plus.
A lot of the Dudleya on Etsy sure do look irregular in a way that suggests wild collection. A few sellers claim explicitly that theirs are greenhouse-grown, and indeed have nice perfect rosettes. Most sellers are silent on the provenance of their plants.
I guess the issue hasn't gotten enough attention for markets in wealthy countries to make rules. Some basic paperwork (e.g., "seller must provide address of grower, and grower must permit audit") wouldn't eliminate demand for poached plants, but would probably decrease it by a lot.
If customers still want the irregular branched look, then that could be achieved deliberately in the greenhouse, with pruning and maybe PGRs (plant hormones). Probably at least five years from propagation to sale, though. Tissue culture lets the grower convert a single plant into an almost unlimited number of individuals very quickly, but each individual still grows at a normal rate thereafter.