It all boils down to one basic concept: confidence and proficiency in operating the aircraft with any level of automation, including manual flight, as deemed appropriate in the situation. Good manual flying skills are no excuse for not being able to use managed guidance properly. And vice versa. Think of the whole spectrum of automation, including manual flight, as of your toolbox. You need to be able to use all the tools safely and efficiently - and, with practice, develop a judgement for which one is appropriate to which situation. The same goes for pretty much anything which involves some variation from flight to flight. If you can do all instrument approaches smoothly but can't do a proper visual, that's one tool less to your avail. If you struggle with flaps 3 landings, here's another tool gone. If you always land with autobrake and struggle to keep the aircraft straight and achieve a smooth stop with a reasonable brake temperature when braking manually - that's again one tool less. And, the more tools you master, the better your chances of solving any random problem safely for yourself and those behind you.