Should I leave my MacBook Air (M2) plugged in all the time?

You can leave the computer plugged in whenever necessary or convenient to do so. Leaving it plugged in will not damage the computer or the battery. An advantage of leaving it plugged in is it reduces the rate of accumulation of battery cycles.

Change Battery settings on a Mac laptop - Apple Support

Batteries - Maximizing Performance - Apple

BeckT123 Said:

"Should I leave my MacBook Air (M2) plugged in whenever it's possible to avoid running battery cycles and in that way protect the battery?"

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Leaving a MacBook Air (M2) Plugged in:

No. I recommend not doing that. Place it in safe a location, when you are away for the day. Whenever plugged in, use a surge protector to protect from power serges or power spurs(typically resulting from lighting strikes and transformer blows).