The weight is likely a wash. Its 2 different items so more opportunities for one being lost/broken. It’s easy to forget the charger. A charger is only useful if you have a place to charge. And finally, a charger means a cable sticking to an outlet, potentially out in public, which isn’t just more annoying than simply having the laptop, but increases the risk of damage.

I’m finding it hard to see a scenario where I would prefer a charger over a little additional weight on the laptop itself.