It's just that he finds them creepy. Here's a snippet with him explaining why.

Shogum and Ginra make a living escorting caravans between the cities across the cursed fields. Ginra can also fly with her magic, but it takes effort.

Ash is practiced in scaling buildings and running between rooftops. He also really doesn't like horseless carriages. Finds them creepy.

The city of Highbridge has elevators to go between the layers of the multilevel city. The main hub is a lot like a subway station, but vertical.

There are carriages, and magitech is at the point where horseless ones are starting to be sold to the public. But most still just walk around.

I'm keeping it vague because I just want to scream into the void right now. There's not much to be done on my end. Asshole is generally getting what's coming to him. I'm just typing this out to process the anger. This is why I wanted to have a happier afternoon.

I’m exaggerating things. Stakes are low, I’m being flowery with language, but it was a bit of a mood whiplash

Lahayne has a small leather-bound planner. It holds the spells she casts, a list of contacts, a journal she hasn’t written in in years and a cheat sheet for relevant legal procedures because even she forgets sometimes. It also functions as a regular agenda.

Shogum always has his shield with him. It was blessed by his god, so he never wants it out of his sight. Plus it helps deal with mages who get funny ideas, and doing so is a show of martial prowess.

Ash always tries to keep something sharp on him so he can catch someone off guard and run away.