I wish more vendors would put "Linux support" on the package. Or maybe "Unofficially supported in Linux" or "Linux community support" if they don't want to get their fingers burned.
Maybe this kind of thing should be enforced in the GPL (as many devices use Linux under the hood).
IME, Linux support is often mentioned on the package these days. But you still need to look it up anyway because it's often a vendor source dump for a particular kernel version. Such drivers are often not that good. Notable exception: my Brother printer-scanner-copier has been working fine with its vendor-provided user space driver for ~10 years now. I think it has not been updated for most of that time. It contains 32 bit binaries!
Maybe this kind of thing should be enforced in the GPL (as many devices use Linux under the hood).