Don’t get concerned about the mismatch in wattages across devices. Safeguards prevent overcharging.
USB-C was developed as a robust multi-function standard that would finally let a single industry-supported jack provide high-wattage power and super-fast data. In the fuss about the transition from USB Type-A and Apple’s original MagSafe and MagSafe 2 magnetic laptop charging system, the joy of a single cable may be lost.
A hallmark of USB-C is that you can plug any USB-C plug into any USB-C jack. The jacks on two devices negotiate what they have in common. Sometimes, this is terrible, like 480Mbps with active Thunderbolt 3 cables and USB-C charge cables instead of 10 to 40Gbps! Other times, it’s great, such as not worrying about the wattage of cables, chargers, or laptops when plugging them all together.
All Thunderbolt 3 and 4 cables connected between two Thunderbolt 3 or 4 ports can pass up to 100 watts. With USB 3.x or USB4 on either end, the maximum could be 60W, but it depends, as with everything.
Read more at MacWorld.com