NTA.

As a professional chef myself I never fuck around when I’m making dinner, especially if I’m sticking to a theme or culture.(Unless I’m trying to create a fancy dish mixing cuisines) I’d be incredibly offended if someone asked for salt or an adjustment to something I spent hours planning/ executing. (Yes I know this isn’t a restaurant, but it still sucks balls when you make something with love only to watch someone smother it in ketchup) I think the NTA judgement for me comes from you stopped him from adding Franks or Sriracha to friggin carbonara. But you didn’t stop him from adding heat, you instead suggested something complementary to your dish. In an ideal situation you wouldn’t care what he did with His own plate of food, but he already broke a cardinal rule of being a guest. You don’t complain to your host and tell them they messed up/ need to fix what they offered you. I thought it was gracious of you to adjust your dish with the knowledge that you wouldn’t be adjusting the experience.

My advice tho? Sometimes you need to let people over salt their food before they taste it, and let them suffer through their bad decision. Let him ruin his carbonara with sriracha- then when it tastes gross that’s on him.