I don't think tools like pngquant should be so easily dismissed. With the pixel density of todays monitors, the lossy changes they introduce can be very hard to see (which may be surprising for those of us who remember the pixelated horrors of Floyd-Steinberg from a couple of decades ago).

For some image types, lossy png has the huge advantage over jpg at the same file size that they have no jpg artifacts.

    671.012 original
    584.677 zopflipng -m
    580.180 zopflipng -m --lossy_transparent
    576.637 pngwolf --max-stagnate-time=0 --max-time=300 --normalize-alpha --strip-optional
    190.598 pngquant --speed 1
    179.638 pngquant + pngwolf