I don’t recall enabling it.

This doesn't load for me on my iPhone or iPad:

https://webgpu.github.io/webgpu-samples/?sample=texturedCube

I dug into my iPad and found a feature flag to enable it, hiding in settings/Safari/Advanced.

So definitely not enabled by default yet.

Confirmed my M1 iPad Pro iOS 18.4.1 also doesn’t have it enabled. Took a bit of digging in the settings app to discover where to enable feature flags too, confirmed it’s off.

It’s disabled still on my iPhone on iOS 18.4.1. Either it was enabled specifically on 18.2, and then disabled, or you enabled it manually. (Or some other weird thing, like it’s only enabled on iPhone Pros.)