And Google Lighthouse doesn't like progressive images. You can have a well-optimized progressive JPEG that renders with just 15% of the data, but you get dinged

And Google Lighthouse doesn't like progressive images. You can have a well-optimized progressive JPEG that renders with just 15% of the data, but you get dinged for not using Google WebP, and your LCP is counted only when it fully loads (this is a known bug, and it died a painful death in a bikeshed of what a "contentful" image looks like.)