Having three computers of different brands in the family (an HP, a Lenovo and a Microsoft Surface), it's certainly been useful in the past to be able to share a single charging port for all computers and most phones in the family.

In fact, USB-C and magsafe are complementary. USB-C is commonly used by displays to provide docking station functionality, so I can buy any display and use it with any computer (instead of having to buy a proprietary docking station that is different for each model). If I'm travelling, I can enjoy the more robust magsafe connector but I can also use USB-C if needed.

It's good because until you invent this new cable, we can have everything work with USB-C.

Not betting on your ability to come up with a new type of charging cable is not as big deal as you imagining it is. Maybe you should come up with a prototype before demanding all type of charging cables be allowed?