Rerun dev here :). Yes, we're using egui with its wgpu backend! As someone else pointed out it is backend agnostic - it essentially generates triangles & textures in GPU friendly way and passes those down to a backend implementation.

All the visualizations like the 3D scenes with point clouds etc. are rendered with our open-source in-house renderer ("re_renderer") which itself is then passing wgpu surfaces/commands to the egui wgpu backend that composites everything together then.

That doesn't mean it's doing any kind of GPU acceleration of 2D graphics.

Given that they don't talk about it in the README, I'm pretty sure they don't.