Tab is a quick way for non readers to get the jist of a song they already have in their head slightly quicker than working it out by ear
It has its place , but is limited
I can't read and only Google for tabs if I'm in a hurry , as you'll always habe to alter it (it's never 100% but can save a bit of time)
Also it's often written with open strings instead of more comfortable positions (for me at least)
If you can read I see why you knock it , but it has some use to many , I remember my first bass book of riffs was in both notation and tab , I had no idea how to read , but the tab got me playing at least .