Hello!
It's true that on an EFIS equiped aircraft you don't use them as often anymore, unless the ILS is of the air and suddenly you get n VOR?DME approach. Then suddenly you have to go back to raw data on one side (as a lot of manufacturers/airlines prescribe) and when you use the old ROSE display, a locator beacon is the ideal tool for closure rate to the radial.
Well, I would say it's third in line for the ideal tools for closure rate, the ideal tool being the flight director
... the second best being the GPS/INS/whatever-position of the NBD and only then the NDB itself.
When instructing, I am still required to teach NDB approches. There are not many left now in our vicinity (none at our homebase). One of them is so poorly calibrated, that on most approaches at minimum you will find yourself right overhead a church spire that is about a mile left of centreline. I have reported this to the authorities more than once already, but they don't seem to care, obviously apart from us trainers nobody uses them anyway.
If you want my vote: Get rid of these things NOW. The sooner, the better. They are the most unsafe means of navigation, because they are both imprecise and difficult to steer by.
Greetings, Max