[ribit]

This has been empirically tested on multiple occasions. There is an article on realwordtechnologies discussing this, and the results have been related for newer AMD GPUs as well. I have a little tool for macOS that tests these things out, and the Navi GPU on my MacBook is definitely a tiler (the Gen10 Intel GPU is not).

[Arelius]

It's brought up in multiple other comments, so I won't bother going into detail, but the empirical testing, is flawed and is actually measuring changes in other details about thread launch behavior.