No doctrine or Biblical theme has been changed in the 1769 revision of the 1611 Authorized KJV.
That's why it's still called the 1611 KJV. If a direct change had taken place it would have been named the 1769 KJV.
If you read up on the revision in 1769 there were printing errors in the original 1611 that were corrected.
Updated spelling and punctuation and the italics were the main focus of the revision.
The content is unchanged otherwise, the reason it's still the 1611 Authorized KJV.