Yes, most files in the modified file list is just because comment style was changed.
So you don't need to update them.
And nothing is broken, even if you don't update any files in other than system/.
As for updating files other than system/, it is exactly the same as CI3. However,
it is true that CI4 is young and still has many minor changes.
Whether you use Composer or not, the situation is the same.
