That is the price I have seen discussed widely. If you want to claim it is not true, offer evidence. The fact is, the UK won’t pay for it because it is that expensive. That is what I understand. But you are welcome to prove that it is actually inexpensive and every healthcare system can’t wait to pay for it.
There are numerous very good sources indicating 21,000 is the cost, and NVCR, like many companies, claims they work with patients to ensure no one need go without, and yet, apparently, many people go without.
In 2016, NVCR charged my grandfather a $20k monthly rental fee for the helmet, and they demanded it back when he died. That was before medicare covered it, and they took his life savings for 10 months of humiliation and burning scalp pain. Now medicare pays about $13k monthly: