I should clarify that when I say “a more commonly used figure”, I mean “among things that have put any consideration into optimisation”. Where not controlled deliberately, tools tend to use the quality of the source image (which is probably around q=90 to q=94), or choose an unnecessarily high value like q=90. But take tools that have put at least some effort into sanity, and you find things like: https://squoosh.app/, a human-friendly tool for manual image optimisation and conversions, defaults to q=75 on JPEG; and the Zola static site generator defaults to q=75 for JPEG <https://www.getzola.org/documentation/content/image-processi...>; and Sharp, a Node.js library used by eleventy-image, defaults to q=80 on JPEG <https://sharp.pixelplumbing.com/api-output#jpeg>.

The considerable majority of images on the web are way higher-quality than they need to be.

I like the images to be at or above quality 94, d1.0 or smaller in jpeg xl. Some other user cares less. Some user thinks that quality 75 is as they came from the camera and it cannot be helped.