In general, not too busy is considered better...but there can be exceptions. I'm a former Risk Manager for a chain of Assisted Living Facilities, and wallpaper that looked like bookcases was sometimes strategically used to camouflage an exit door, to reduce the chance of resident elopement. (But not the main door; and not the entire hallway; just perhaps a section with an emergency exit that shouldn't ordinarily be used.) A little trompe l'oeil.

It’s my understanding that busy patterns can cause confusion and anxiety

Wow. I think it's a good thing that there's a lot of plain-white painted woodwork, to offset all the pattern. They're certainly not trying to camouflage anything!

Helen5. See video below. I’ll be interested in your opinion

Doesn't seem to be calming.