Outside of certain metro areas, US Judo instruction can be pretty bad too. The question is, what is BJJ doing right that teaching standards is more uniform?
I believe it is a business model thing. This is the elephant in the room in all the discussions about BJJ pricing.
There are three main grappling arts widely available in the US: BJJ, Wrestling, and Judo.
BJJ is supported by private citizens. It is very accessible, but also pretty expensive. It is the model everyone loves to complain about.
Wrestling is supported by public institutions. Schools and universities put a lot of money into the sport. It is not very accessible outside of these institutions, but it is close to free within them.
Judo is not supported by private citizens nor public institutions. It actually has very little support at all in the US. It is not big in schools, and nobody wants to pay for it. It is very accessible, but it is not valued.
If you look at the caliber of US practitioners of each art compared internationally, Judo is far and away the weakest. One of my old Judo instructors used to train at the OTC, and he told me firsthand of how the entire US Judo team would get manhandled by regular Japanese university teams when they would travel. It wasn't the Japanese national team handling them; it was just regular guys from Japan who weren't even close to making the team.
My instructor used to complain that there was no way this was ever going to get solved as long as people in the US refused to value Judo. Japanese institutions clearly value it (it's similar to Wrestling in the US), so there is just no way the US can ever hope to be competitive.
BJJ and Wrestling both have motivated, professional level coaches existing in the US. And elite international competition opportunities exist for those who want to go that route.
Judo instead has a very checked out, volunteer, part time instructor corps. Elite international competition success is extremely limited. Some would say it does not truly exist at all.
If the BJJ business model changed to the Judo business model, you could kiss most of the high level BJJ in the US goodbye. Some truly elite level guys are willing to train for free. Terere is an example. They want to do this in Brazil though, not in the US.
The quality of instruction directly correlates with the value practitioners place on it. This is reflected pretty clearly in the prices. BJJ is expensive. Wrestling is expensive too; it's just harder to see how expensive it is because it's funded by larger institutions and not private tuition. But those mat rooms and facilities are far from cheap.