I think the argument is that if you write a 1 with a line at the bottom it is easy to confuse it with a sloppily written 7, whose bar moved down a bit.
Which invalidates the argument of the user above. (If not inverse it - a lot more numbers in life start with a 1 than with a 7)
Me neither, but I also don’t read a lot of handwriting from other parts of the world. But I have heard that some places teach the 1 with a horizontal bar and the 7 without one.
Pew pew (slrpnk.net)
Yes. We're better than you. (startrek.website)