In May 2021 Google will be changing its SEO and SERP algorithms to favor websites that load the quickest. In order to prepare for this change, one can use this tool to get a feel for both mobile and desktop issues:
https://developers.google.com/speed/pagespeed/insights/
The results for all of the websites I manage yielded this:
"Serve images in next-gen formats: Image formats like JPEG 2000, JPEG XR, and WebP often provide better compression than PNG or JPEG, which means faster downloads and less data consumption."
I'd love it if Affinity could could incorporate these formats in to Photo.