I tried it and it didn't work. Downloaded Safari Technology Preview on my 2023 MBP and it returned various errors in all the WebGPU demos I tried.
From the preview page:
To enable WebGPU, turn on the “WebGPU”, “GPU Process: DOM Rendering” and “GPU Process: Canvas Rendering” feature flags in the Feature Flags tab in Safari Preferences. If you don’t see the Feature Flags tab, you need to first check “Show features for web developers” in the Advanced tab.
Same here.
Took a beat to realize I was looking at the OP and WebGPU demos in Safari.app instead of Safari Technology Preview.app.