It’s definitely not full OOTB on any machine using Broadcom wifi/Bluetooth, and sometimes not even Ubuntu’s additional drivers tool is of no help — if you have no reasonable access to alternate network connections (hardwire, tethering, etc) you’re stuck ferrying around .deb files on thumb drives and such.

There are other less than ideal aspects of taking up Linux as well, but that one is on the top of my head because I’ve encountered it so frequently.