Hello,
I am the creator of the Golden Age of Air Travel 1958 navaids package referenced above.
I find the topic of having historically correct navaids very much relevant for old aircraft (be it from 50s, 60s... or 90s). So I am happy to see JustFlight is aware 👍
My 2 cents...
Data
Data are there but in very different formats (paper charts, lists, tables), not georeferenced and from different time periods. You want to have reliable data covering all navaids from one cut off date. Not easy to find. And then there's gaps in data like missing ranges etc.
Workload
It was a lot of work. A lot. It is not only about having a source but actually it was a challenge to get it into the sim. If you are interested about the workflow, check the thread here:
https://forums.flightsimulator.com/t/released-u-s-golden-age-of-air-travel-1958-navaids/629250
Commercial potential
It is just not there.
I got a few very positive and heartwarming feedbacks but the package has got only some 160 downloads from fs.to (no updates yet so these are pretty much unique downloads).
So such a project is clearly a niche within a niche.
Other considerations
Navaids is just a part of the full picture. Such a scenery package should also contain period correct enroute planning charts (VFR and IFR), approach charts and for 1960s+ periods also SIDs and STARs in order to be able to replicate the flights in their full glory.
Many runways are gone as are some airports... etc.
My take
I would buy such navaids sceneries in a heartbeat. If I turn it the other way around, I will probably think twice before I get a 1970s or 1980s aircraft because I think without putting them into their historically correct context it makes little sense (to me) to fly them.
In the end, I made the 1958 navaids scenery because I wanted to fly the DC-6 as it was meant to be flown 😀
Milan