By continuously installing/uninstalling the competitor's app they can even make their business unsustainable. And more, what would stop apple from hiring a third party to do that, just to inflate their own profit?
Apple mentions it in their FAQ, and says it's a thing they'll be watching out for: https://developer.apple.com/support/dma-and-apps-in-the-eu/#...
If you've seen people say updates cost money, it's because an update counts as another installation of the app. But because you're only billed for the "first annual install", this just means that someone who installs an app and leaves it installed for years will still wind up counting against your annual install-count so long as you're updating that app. You can release an update of your app every day of the year and it won't cost you anything extra.
Sure:
https://developer.apple.com/support/dma-and-apps-in-the-eu/#...
And from the FAQ:
"What is Apple doing to prevent ‘install bombing’ — efforts from bad actors to increase install numbers to increase the Core Technology Fees developers owe to Apple?
Already, Apple takes a number of steps to prevent fraud and scams and protect developers’ intellectual property. Apple is implementing additional measures to monitor, detect, and prevent install abuse, including:
An install verification mechanism to ensure all installs come from real Apple devices
Limits on the number of first annual installs that can come from a single device Investigating, and potentially terminating, user or developer accounts that engage in suspicious behavior"