I don't see how it'd cause lazy eye. Speaking as someone who had emolicious hair that often covered one eye, somehow I could actually see through my hair.
I dunno how to describe it, but yes, I could see beyond the hair covering my eye. Sure, it got in the way and obscured my vision somewhat, but I could still see stuff in front of me with that eye alone. Not only that, but I was also capable of (gasp!) switching which eye was the one being covered on a daily basis! And not only that I could (double gasp!) move my hair so their NEITHER eye was covered!
So frankly, I call shenanigans.