The wipers are automatic and initially (like 18 months ago) they weren't good. But instead of asking "why couldn't they put simple tactile wiper controls" a much better question was "Why can't they train a neural net and make the car smarter so the wipers work better than manual controls?"
And the answer was, yeah they could. And they did and today the wipers are quite good.
I get that I am an outlier compared to most Tesla owners who weigh things differently. I'll just be glad when there are alternatives at the level of battery, drivetrain, and mechanical & aerodynamic efficiency of a Tesla that take a different tack on controls, interfaces, and remote access.
But I agree with @null_turkey - after the Model 3, it's clear any vehicle I would buy next for daily or near-daily use would not have a pure ICE drivetrain; at a minimum, it would need to be a plug-in hybrid.
My S and X both have "normal" wiper controls on a stick attached to the steering wheel, although I almost never use it since they are set to automatically turn on and change intensity depending on rainfall.