It depends what the subject matter is and where it is going to be shown, imo.
Much like DOF scales, viewing distance is just a rule of thumb and not written in stone.
Will a 13 x 19 ony be viewed at 2 meters or whatever the "rule" says. Maybe yes, maybe no.
If your prints are hanging in a gallery and are of subjects such as a landscapes which contain lots of fine detail, people will put their nose against it, since that type of subject draws people in closer and closer to look at the detail, or lack of.
If it's a shot of a person, people expect to see individual hairs resolved... the rest doesn't matter as much. I assume the eyes are in perfect focus and detailed.
If it's going to hang in a hallway/staircase, then the space available to back off is limited so you are forcing the viewer to be close.
If the image is going to be used on some cardboard promotional card standing on a store floor, people do not expect razor sharp images, so less is acceptable.
I have some large prints from P&S's that I took many years ago. All are "sharp" on my screen. Some you could put your nose against on a 11 x 17 print, others I threw out because they looked like crap at 8 x 11, no matter how I tried to process it.
It also depends on what you print. When in doubt, print on canvas, who's ability to resolve fine detail is the lowest of all mediums. Not all images lend themselves to canvas so that may not be an option.
So, to answer your question, it depends.