Maybe when this crisis is over, those Linux devs should come one day earlier when trying to do presentations on our beamers, instead of showing us the configuration mighty of xrandr.
It's the other day around. You should be asking them what beamers they would be able to use on their Linux systems with good support and that does not require complicated tools, instead of buying something that is not supported (yet!) and claiming later that Linux is crap because it doesn't work for your particular type of hardware.
Except at the end of the day catering for 1% of the desktop is too much to ask for to cripple business operations with, when 99% of everyone else is coming in with Windows and macOS laptops.
If by "capability" you mean not supporting some latest standard that provides marginal benefit over established solutions (e.g, Wi-Fi b/n/c/whatever, "cloud printing") or anti-features (Apple's "Pro" touchbar), then yes. But if you mean being able to do anything actually useful, I'd say that maybe only those working with Audio Processing still are under-served by Linux Desktop - and even that will change soon with Pipewire.