Because I am trying to help, not set people down a path of discouragement. You have to learn to crawl before you walk.
If that is the case, then IMO, it is disingenuous to suggest to a newbie that Manual mode is only to be used when their more advanced or experienced. We're still only talking about three things here.... Aperture, Shutter Speed and ISO. Regardless of which shooting a person choose to begin their learning experience with, these three things must become learned to the point it becomes second nature as to why one setting over the other is used to capture the shot you envision. You may still miss the exposure, but you'll understand what would've been the better choice. Likewise, you can look at the exposure and do a Homer..... D'Oh and realize what you forgot to check before the shot. I would hazard a guess that someone just starting out and shooting in Manual will have a greater understanding of the exposure triangle than another person with the same mental faculties starting off in Aperture mode. Granted, person A would probably have more duff shots in the early days than person B, but that is what practice is all about.
Do you practice when you've got to get that (I love this term) "Once in a lifetime shot"? Hell no, if you're not confident enough, put the damn camera on auto-pilot and let it rock. You practice when you're alone with your own thoughts and just like a music student, you run the scales up and down and up and down and up.... I think you may get my point. If a newbie doesn't put in the time and energy, they will stay at an acceptable to above average level for their immediate circle, but mediocre to below average on one of these photo forums. Even a blind pig will find an acorn. You gotta pay yer dues brother.
Me, I couldn't give a rat's ass what shooting mode anyone chooses. But I think it is a disservice to discourage.
I think this has gone further than I expected and apologies for the verbal diarrhea, but blame it on Agent Drex.