I'd say that progressives may not be right for beginners who have no mechanical aptitude or the patience to read an instruction manual. Otherwise, there is nothing fundamentally harder about a progressive, it just does all the same steps at once. I'd argue that setting up a progressive and moving through the stages is just as good as torturing yourself with a single stage going step by step. The progressive v. signle stage argument would be like saying that you shouldn't buy a car with a radio when you first start driving. Okay, it could distract you but you can also just turn it off until you are ready. Don't get me wrong, single stage presses are great for pulling bullets and sizing odd-ball brass.
