I have a 2011 MacBook Air. Are there technical/physical reasons why it might be harmful to have the screen repeatedly touched or pressed? Why or why not?
From my experience, pressing the screen can't damage the mac's interior, unless you're pressing very hard on the screen, but scraping the screen with you're nail is bad for your device. DO NOT scrape on the edges of your screen or dig into the bit inside the edge of the mac's screen. I would overall advise not to touch or scrape your mac with your nail.