Just wondering. Also, I don't recall McCartney officially endorsing Hofner. Are there any ads floating around?
Very well said and I believe this is the answer. Being a guy that grew up loving all things Fab, I purchased a 500/1 back in my playing days. I loved the little bass. Didn’t spend too many nights on stage with me though as it just didn’t have the range I was used to. It was a novelty to me used when we played Dear Prudence for the visual aspect. It was relegated to my music room wall for five years when another star crossed McCartney guy offered me near twice what I paid.... I agree, if Macca hadn’t brandished the Hofner as his trademark bass, we likely would be seeing them in the same way as Danelectro’s and Silvertones and such.You're asking two questions: Hofner--as a company--is a long-established German instrument maker (orchestral strings, acoustic and electric guitars, electric basses). They'd probably be around with or without McCartney.
The more pertinent question is: Would the Hofner violin bass still be around if it weren't for McCartney. Possibly not, I think, as the pervasiveness of Fender may have relegated it to being a 50s/60s novelty, like quite a few other unusual designs from the era. (Although the other Hofner basses that didn't get a direct McCartney boost are still around...)
However, as commercially lucrative as it was/is, there's a dark side to the McCartney association. In many cases, the violin bass has been relegated to a nostalgia piece by people who want 'a piece of Paul.' That, in turn, has pushed Hofner to mostly make replicas of the old 500/1, rather than advance the design.
The 500/1 is, for many reasons (none of them having to do with the Beatles!), my favorite bass. But it could stand some updates: a more readily adjustable bridge, larger tuner shafts, and a more flexible control panel. The control panel is a good example of how consumers froze this bass in amber: According to Hofner, the company tried to update the controls at some point, and customers demanded it be returned to the original limited switching arrangement. So even the company knows it's silly, but unfortunately, the customer is always right (except when it's not).
That said, I've rewired the control panel on my violin bass so that it offers much more tonal flexibility and excellent pickup blending options. In a perfect world, Hofner would update a few aspects of the 500/1's design themselves, while still offering offering a few retro models for collectors/Beatles fans.