+1 on this one.
I possibly don't need it, but it would be useful to have. All I'm doing in my setup is to turn autosync on/off upon various triggers, but to me it seems wasteful to instruct Tasker to turn autosync on when it is already on... for me it would seem preferable to turn autosync on only IF %AUTOSYNC != ON already.
But perhaps the "turn autosync on" action would do that check anyway "under the hood", i.e. do nothing if it's on already?
Regardless, an %AUTOSYNC variable would doubtless be useful for other applications. I'll take a look at the workaround suggested by TomL.