GPU accelerated versions are imperfect (based on Adobe and Apple’s experience). GPU acceleration is suitable for previews or working copies, not for masters. The most efficient workflow with DxO PhotoLab for multiple output resolutions is to output a set of masters (either a TIFF for 32 bit but much more space or a zero compression JPEG) and then use a dedicated resizing/watermarking application to create the other versions.
The issue with using DxO PhotoLab to create multiple sizes is that each version requires full processing from original which can be very slow (as slow as 2 minutes per image). Working from TIFF masters means even huge resizing and watermarking jobs are done in 10 or 15 seconds per image.
Moreover, each of us can choose the web prep script or application which suits us. Some people have really high watermarking requirements, wanting both visible and invisible watermarking - or others want all kinds of changes with GPS location, EXIF data and renaming - or others just need fast simple high quality resizing.
GPU acceleration for the preview when working with sliders to allow us real time sliders would be a gamechanger in terms of workflow and in terms of attracting professional photographers and retouchers to DxO PhotoLab and other products.