I don't think that's true.
Usage is different. charging you leave it somewhere and let it do its thing.
laptop sits where you use it so you keep it plugged in often and when go mobile,d disconnect.
same with fragility. if you drop a phone with a case on a carpet, might be alright. a fragile screen with a big drop and thinner, maybe not..
That's the point Apple is trying to make with this new macbook - usage is different now.
Keep it plugged in at the desk when you're working, you probably don't need to worry about it falling there. But you don't have to look for an outlet anymore when you're on the go. There's no need to plug the laptop in at the kitchen table and string the power cord to the wall - there's plenty of battery life now.