If it’s deletable, it’s fine. On iOS and Android, you have to jump through serious hoops to be able to delete something that would make the OS break, and if you’re asking this, you haven’t jumped through those hoops.

The hardware won’t be damaged by removing software or files. Worst case scenario, any faulty hardware might give up the ghost while deleting things, but if the device is that far gone, it would happen no matter what you were doing. It’s kinda like driving a car with a bad belt; idling at a stoplight isn’t going to be any more likely to make the belt snap than idling at home.

You deleting a file is no harder on the device than making a phone call or using an app. Same with uninstalling something. If something like the RAM is going to die, it doesn’t matter what you’re using the memory for, it’ll go when it goes.

You have nothing to worry about unless it’s something vital to the operating system; but you would likely be unable to even SEE those files if you haven’t rooted the device.

The size of the app doesn’t matter, it’s what the app does.

Say you managed to uninstall your only launcher. Getting a new one on there would be a pain, but is doable. But uninstalling the fucking massive DJI app? Nah that’s nothing.

Think of a file system as a book. There is a table of contents, and then all the files are in the subsequent pages. Deleting a file is typically done by removing the entry in the table of contents, the pages are untouched, which means its a very minimal change.

Deleting an app should be fine, but if its an older phone, you may want to look for a migration path, as hardware will fail as it ages. Could be anything, battery, charging ports, buttons. One day it will die.