Canon is generally fairly conservative with its update timeline. Being the EOS R is a first-generation product, it’s difficult to judge how long it will survive, but the construction is solid, it’s entirely weather sealed, the specs are more than adequate for most situations, and it has the new RF lens mount, which is where Canon will presumably pour most of its future research and development into.
Should you buy it?
If you’re a Canon user who’s been looking to hop onto the mirrorless bandwagon, absolutely. It not only works with all of your EF and EF-S lenses, it actually breathes new life into them with improved autofocus capabilities and unique features introduced by the adapters. It will also feel familiar, both physically and in the software user interface. It’s just enough change to push Canon into the next generation of cameras without alienating its longtime fans.
However, if you’re a first-time camera owner looking for a mirrorless camera, it might be worth it to look around before settling on the EOS R. Yes, it’s a great camera for stills with reasonable specs, but there are far better cameras out there for video or more niche use cases