Some Xorg WMs are just slow. I've noticed fluxbox can take it's time opening new windows while FVWM does not. There's probably something similar going on with Phosh. Then there's loading all the SOs and whatnot that might not be cached.
I highly doubt GPU acceleration has much to do with it. It might even make things worse by taking memory that could be used for disk cache and using it for compositing instead, but I don't know enough about the pinephone hardware to really know for sure.
I highly doubt GPU acceleration has much to do with it. It might even make things worse by taking memory that could be used for disk cache and using it for compositing instead, but I don't know enough about the pinephone hardware to really know for sure.