Every camera manufacturer that shoots RAW invented its own file format. Canon has CR2. Nikon has NEF. Every serious camera on the market writes its sensor data into a container that only that manufacturer’s own software, or software that manufacturer chose to license the specification to, can reliably decode.
That has been true for years, and photographers have mostly shrugged about it, because the software to read today’s files exists today. The part worth worrying about is what happens to a file shot this year in twenty years, when the camera that made it is a museum piece and the manufacturer has moved through several generations of format revisions since.
Adobe has been pushing an answer to this for a few years now: an open specification called DNG that any manufacturer could adopt, documented publicly enough that decoding it doesn’t depend on any single company staying in business or staying interested. A handful of manufacturers, mostly the smaller ones, have adopted it as their native format. The two largest, Canon and Nikon, have not, and I do not think that is an accident.
A proprietary format is a small but real form of lock-in. If your entire archive is shot in a format only one company’s tools can open properly, you have a reason to keep buying that company’s cameras and that company’s software, or at minimum a reason to think twice before switching. An open format removes that friction, which is precisely why the companies with the most market share to protect have the least incentive to adopt one.
I do not think this is a crisis today. Current RAW files convert to DNG without much trouble, and the major photo software still opens formats going back years without complaint. The risk is cumulative rather than immediate. Every year a manufacturer’s own format persists as the archive standard is a year that photographers’ files depend on that company continuing to support decoding a format from a decade or two ago, for a customer base that is not paying them anything for the privilege.
My own practice, for what it is worth, is converting to DNG on import and keeping the manufacturer’s original alongside it rather than instead of it. That takes more storage and more discipline than most people will bother with, and it is the only approach I have found that doesn’t require trusting a single company’s roadmap with photographs I still want to have in thirty years.