Yes, iPadOS has deep, lingering deficiencies as an OS for professional use.
But their ads and keynotes are convincing, so I can't blame people falling for it! There's this weird juxtaposition of a terrible productivity machine combined with some mature, amazing and easy to use software in the demos, and Apple makes it look like iPads can be deeply embedded in your workflow and people have fun and laugh as that tiny device with its M1 CPU is a heavy lifter even for 4K and professional audio mixing.
And everything looks good at first sight. Until you reach the final 5% of usage where you either 1) need to interact with other software, 2) other storages like a Mac main storage, NAS, Samba, NFS drive, personal cloud etc, or 3) just somehow move out of (and back into) that sandboxed app for any reason. Then everything falls apart. Yes, even with that Files app.
There are tools and methods to exit the sandboxed app (share sheets omg all the share sheets) but it's just painted with bold letters all over the place that this is not what iPadOS was designed for from the ground up, but it's in fact still just a smartphone OS with a brand change and some special purpose features added on top that you can run on a device with a large display.
When Apple announced the iPadOS brand, I thought "Wow they finally get it" but I don't think they can figure this one out. They've had so many years now and we still have articles like these. I want them to figure it out because a slick system with optional keyboard and mouse sounds great to me.