Maybe I'm buying more sturdy laptops than your daughter gets, but I've never broken anything by doing that, and I have laptops well over 10 years old, and have been doing that for some 25 years.
I understand the theory, but I think significantly more laptops are broken by e.g. squishing them against a non-flat object in a bag, or dropping.
Think of a modern tablet. Would you seriously say one must not hold a tablet by an edge?
(Me personally, I destroy all my laptop hardware by spilled drinks...)
I've never knocked a computer off the edge of a table because it was left with part of it extending beyond the edge. But leaving it like that does make increase the risk of that happening. The same idea is true of picking it up by the edge; it increases stress on the hardware, which can cause damage. The fact that it hasn't happened to you just means it's isn't _sure_ to cause a problem.
I understand the theory, but I think significantly more laptops are broken by e.g. squishing them against a non-flat object in a bag, or dropping.
Think of a modern tablet. Would you seriously say one must not hold a tablet by an edge?
(Me personally, I destroy all my laptop hardware by spilled drinks...)