Some games just add an update pak that overloads the changed files, not changing the original pak file. So the installation size of such games might grow a lot

Some games just add an update pak that overloads the changed files, not changing the original pak file. So the installation size of such games might grow a lot on updates, wasting a lot of space by keeping the old files, but the files are immutable at least and rollbacks of updates are theoretically possible.