Your are saying grand parent is mentally a children, I don't how this is perceived in your culture, in mine it is not acceptable.
Its childish to label other people as children unless they happen to be children.
In that case it's bad to call someone childish because some of the best features of humans are only apparent for most people when they are children and not adults, but that isn't the point of what was said.
The point was that it is short-sighted of someone to say it would be evil if (say) Apple won the mobile war, but would be good if Google won the mobile war. Competition is a win-win situation for consumers, and a lack of competition only encourages stagnancy, which is one of the greatest evils of the creative world.
Because people like this are hypocrites… they want to take your choice away, and scream and fight and claw madly if they don't get their choice.
Mentally, these people are still children. They look at everything (e.g. alll of business) as it if it is a zero-sum game. They take everything personally.
It's hard not to be offended when you think a phone OS is tied intimately to who you are. Sad, but true.