Have you tried doing this when your MacBook is plugged in and not less than 20% battery?
When the power is critical, macOS likes to be stingy with where it allocates power, and USB is often one of the first things it cuts. Another issue that could be preventing your camera from connecting is the type of cable you're using. Believe it or not, there are several kinds of USB C cables that don't all do the same things. Some are power only, others transfer data very slowly, some are "normal," and others are Thunderbolt-rated. You don't need a Thunderbolt-rated cable, but you need a decent one that transfers data and power.
If you have tried a different, quality cable, and your MacBook is plugged in, and you're still having problems, give our team a call so they can troubleshoot with you. Support is at 800-OK-CANON (800-652-2666), Monday through Friday.
