Mahfuz is definitely best to respond here.
There was one interesting study recently of 120,000 Chinese school children aged 6-8 that showed an increase in short-sightedness during the COVID-19 pandemic. It's important to remember we don't know if this is because of increased screen time or less time spent outdoors in daylight (or both). It's also worth mentioning this is short-term data so follow-up would be needed to see if these changes are significant over time (can our vision easily correct itself? are the effects the same for older children and teens?).
Not gaming or IGD specific but thought it still may be of interest as it pertains to eyesight.