You can’t truly optimize an image for every uncalibrated device, because viewers may be using wildly different screens, brightness settings, color modes, and viewing conditions. The main goal of calibration is to ensure you are editing from a known, reliable reference—not to predict every bad display.

Practical advice:

• Edit on a calibrated display so your file is consistent and correct at the source.
• Choose images that are naturally robust on poor displays.
• Prefer bold, simple images over ones that depend on subtle tonal or color differences.
• Avoid scenes where important detail sits near pure white or pure black, since weak displays often clip highlights and shadows.
• Avoid images that depend on delicate cool color balance; a warmer image is often more tolerant of color shifts than a cool image that can turn unpleasantly blue.

In short: don’t try to chase every possible bad screen. Create a well-prepared master on a calibrated system, and when possible select or process images with strong separation, clear subject matter, and less reliance on subtle tones or fragile color nuances.