I didnt mean to imply that the perception is entirely fair. Infact, I think everyone should take a sabbatical and for more years. It helps in your personal growth which enriches your professional approach.
That being said, the red flag is how recruiters see this. And no argument on the internets will change this perception. Recruiters spend a lot of time and money hiring tech workers - the last thing they want is any indication that the guy is not 'stable'. Its a demand/supply problem.
The only 'solution' to this problem is if everyone starts taking sabbaticals and it stops being a big deal.