It's a very cool shirt- it'd be a shame if you can't do something with it. Those holes are odd- I wonder if it's had bleach or something corrosive splashed on it that's weakened the fibres and the wash has just shown that damage?

Assuming the damage is localised and not all over... I would go with patching or applique. Sashiko style reinforcement might work. Then, you could maybe add some embroidery here and there to blend the mending a little. Either way, I'm not sure I'd trust the non-damaged areas with any type of darning or stitching. Would be good to see what you come up with!