Is it rude to not tip at a coffee shop if I just get a pastry and black coffee?

I got coffee this morning and the barista pours it and grabs me a muffin. eleven seconds tops. then the tablet spins around and it’s already sitting on 30% by default. you have to actively hit custom and type zero. I normally tip when it get coffee but atp it’s getting insane and I’m not tipping $4 for 10 seconds of work.