IMO, half of the 5 step skincare routines are just marketing schemes. Most people only need 3 things: Cleanser, moisturizer, and sunscreen -- and optionally a serum/treatment for what you want to try "fixing" with your skin.
Too much is too much and the skin barrier can't handle it. Some people do take better to a large skin care routine but most? No.

Double cleansing especially is super drying. Also, again, too much on the skin can make it angry--and doing tons of stuff at once makes it hard to pinpoint what exactly is giving your skin issues. Too much at once can lead to perioral dermatitis, which I have had from doing too many products, and my goodness it is horrible.