ADF and a fixed card was a great tool for training ab initio pilots, it sure weeded out those who could not multi-task and paint a picture in their brains of the position relative to the ADF bcn or RWY. I did my share during training with intercepts from all kind of directions, entering holding patterns.. Using the RMI made life a lot better.
In actual airline flying, in 30 Years of airline flying, almost all of it on heavy jets, I might have flown 3 actual NDB approaches in not so good WX.
During the 17 Years as capt I started my non-precision crew briefing stating we had an emergency coming up
That got everybody's attention.
Flying any non precision in a heavy jet is outright dangerous, enough terrible accidents have proven that. Just one wrong frequency and You got completely lost.