Nasus is a terribly designed champion
You can't beat a Nasus, you cant stop him from stacking because of how stubborn they are, if you do manage to bully him and make him loose out on farm you will just have to waste your lead in lane or following nasus around making sure he doesnt stack, and if you dont he will just free farm. You cannot 1v1 him besides late game Fiora, you literally need your whole team to come and stop him if he is a head since his damage output and tankiness is absurd.
I cant be the only one who sees this, and unless you pick
with
you have no hope of stopping him late. and every nasus main bans quinn
[sg-ahri-1]

you win lane, you push him out lane and you able to secure two towers but cause your team super weak you can't close from staying top cause Nasus or Tryn will safe farm with help from their jungler and if you moved to help team there the 50-50 chance of winning or failing which lead the split pusher to win hard and scale if you failed to close it as team.
.
. She thrives on mistakes, but if you know how to play against her you should win. It takes still and knowledge to actually kill her.