Adding customer types to multiple customers doesn't have any limitations, matt8. I've also checked and found no reported issues about it.
The Batch actions feature is the easiest way to add a customer type to all customers at once. Since not all the profiles get updated, we can try a couple browser troubleshooting steps.
To start, kindly close and reopen QBO to refresh the program. Once you're logged in again, assign the customer types. If you get the same result, access your QBO using a private browser. If it works there, go back to your previous browser and clear the cache. This issue is probably caused by the stored files from other sites you've visited.
You can also assign the customer types using Google Chrome, Internet Explorer, or Mozilla Firefox in case the steps I gave don't work.
Feel free to get back to me if you need anything else. I'll be around to help.
