I will do it on either, though I am mindful that the side stand is not as robust as a Commando. My Triumph will light
up first or second kick every time. If I had trouble kick starting it I most certainly would put it on the center stand.
Some will call me a fool for ever kicking it over on the side stand.
I personally never use either stand to start my bike (a one-kicker) except while checking ignition timing dynamically - then I'll kick it once from the side with it on the center stand.
How badly a side or center stand is damaged by kick starting would probably depend upon one's body weight and technique. Using the side stand is particularly problematic because over time it will tend to bend the lug on the frame.
I open both taps, hold bike upright no stand. One kick choke on, 10 seconds, turn off choke. One or two revs to 3k or so. Close reserve tap. Go. MKIIs and Pazon. On occasion, I'll start on the center stank with me standing aside the bike. Never put my weight on the side stand. Its not made for that.