The command line is a problem for intermediate users. I consider Linus from LTT to be at the upper end of intermediate and he was borderline incompetent in Linux. When you have enough knowledge to be dangerous and the hubris to assume you know everything you should need to know, you will find yourself in deep trouble quickly.
The most computer illiterate will be fine, but they will not be buying a machine like this. The most advanced people will probably be fine mainly because their expectations will be in check. I'm personally having a hard time getting my 13 year old to debug issues in windows and linux because his expectations are just too high (probably years of ipad use). He expects things should just work and get frustrated too quickly.
Anyway, I think success in linux is more mental than anything. The terminal shouldn't be the frightening thing people like to think it is. It's just FUD. I'm in the terminal all the time on my Mac and no one seems to have an issue with that.