One challenge with PNR is actually restricting the alphabet appropriately. They sure are easy to say aloud -- just five or six letters in many cases -- but how do you ensure you have (a) enough letters to get a reasonable bitwidth and (b) not form ridiculous words?
Take all the Roman alphabet apart from the vowels - 21 characters and length 6 gives you 100 million possibilities which is plenty for most applications.
You can still get vaguely offensive sequences like FKNNGR or BLKCNT, but at some point you have to put this down not to your software being offensive or hateful but to humans finding patterns in randomness.
This is just not going work in a customer centric organization. If SABRE gave out PNRs like, I don't know, SEXGOD, it would make customers angry, and that is not even with any curse words. They are heavily filtered.
For example https://sqids.org/ ensures that there are no profanities in the generated ids. And it allows you to add additional words that you want to avoid.
It does but it allows common names, the name of the deity, common words, &c. I suspect you have to do something like an earlier poster suggested -- strip out all the vowels to start with...
