When I first became interested in photography, there were no digital cameras. For casual snapshotters a simple film camera was the only choice.
Serious amateur photographers, like myself, bought single lens reflex 35mm cameras which took interchangeable lenses. Professionals bought cameras that took 120 film in rolls or even cameras that took sheet film. The larger the negative, the better the quality.
The earliest digital cameras were generally a novelty. They could only record a handful of pictures which were of poor quality.
It didn't take long though for things to improve. Better sensors allowed photographers to print in ever increasing sizes and then came the digital single lens reflex which were a hit with serous amateurs and some professionals.
The main aims were to increase the number of megapixels which improved resolution and to make the cameras work in ever decreasing light. At the same time, things became more and more automatic- auto exposure, auto focus etc etc. These features allow photographers to concentrate on composition and framing and take photos in situations that would previously have been impossible..
The death knell came though when mobile phones started to include cameras that took remarkably good photos. You no longer see people pointing cameras at their subjects, they whip out their phone to do the job.
As in any field of electronics, development and research costs money and that cost has to be recouped. Sales of cameras are in decline and the fewer people that buy cameras, the more expensive they become. The newer version of my main camera cost 3,500 Euros when it was introduced - way more than I can justify spending.
I can't see me taking photos at concerts with a mobile phone but who knows, in the future that may be the only viable choice.