Why `eye` has been deprecated?

One thing that I do not like about I is that it is not an AbstractMatrix, but is considered a scalar for broadcasting purpouses. So while zeros(3,3) .+ eye(3) does exactly what you think it does, zeros(3,3) .+ I is equivalent to zeros(3,3) .+ 1.

(In this particular case, one could use + instead of .+, but that does not work in general.)