You can still use USB-C for charging macbooks that have the new Magsafe, just like you could with any macbooks since their introduction of USB-C.

Not sure what you were trying to say about everyone suddenly needing to get a new set of chargers either. I have two different M1 macbooks in my household (one from my workplace, one personal), charging both primarily using Magsafe, and have spent exactly zero dollars on "a whole new set of chargers". The magsafe charging cable that came in the box with the device seems very sturdy and has shown zero signs of issues in the past almost-2 years. Never felt compelled to purchase another magsafe cable either. And the new Magsafe cable has USB-C on the other end, so I can use it with any charging brick, and it will work just as well as with the Apple ones (provided the brick can output enough charging power to deliver the full charging speed).