Based on decades of experience, I do not agree one bit.
Pro Tools isn't the only DAW game in town, in fact its not even the most commonly used any more and its also not the 'best' DAW for many jobs - merely the most entrenched in peoples minds as a "pro tool".
So many producers are giving it up for cheaper and more effective tools such as REAPER, which not only runs circles around Pro Tools but also runs really, really great on Linux. As does Ardour, which is easily in the same class of any of the other DAW's in terms of capabilities. See also, Waveform, Zrythmn, Qtractor and MusE.
As does BitWig Studio - an Ableton Live analog, arguably more powerful and feature-rich than Ableton Live, which makes sense as it is being built by ex-Ableton folks.
FL Studio? LMMS! Renoise!
Linux Audio really rocks.
Not to mention: ZynthianOS! Oh my! Monome NORNS! Holy heck!
>one major DAW
Sorry, no, this is wrong. REAPER is a major DAW, runs natively. Same with BitWig, Ardour and Harrison Mixbus. So thats at least 4. [1]
>very few plugins
I challenge you to actually install Ubuntu Studio and repeat this claim. Plus, VST plugins run great under Ubuntu Studio. You should probably try it again and update your understanding of the scene - you might've had a point 10 years ago, but as of today: just no. Linux audio is amazing.
>I still think Linux audio is a disaster.
I think you don't have enough modern experience to make this claim. My Presonus-based Ubuntu Studio DAW is the lowest latency, easiest to use and set up DAW in the studio. While the other producers are cussing through the hoops of eLicense and dongle management and unsigned/outdated kext's for super-expensive boutique/cocktail hardware, the Linux DAW users in my studio are happily whistling through the edits with their USB and Firewire-based audio i/o devices, many of which work quite happily 'out of the box', "apt update && apt upgrade" dilemma notwithstanding ..
[1] - If these DAW's can do it, there is technically no reason the other DAW's can't - its just the fixed idea that "linux audio sucks" that prevents this from happening in the industry.
Linux audio does not, in reality, suck - it actually ROCKS, hard. Linux audio only sucks if you say it does.
There are certainly no valid technical reasons for a lack of ports from the market-mindset vendors .. just the mindset you proffer, which is, imho, plain wrong.