Not quite sure what you're saying; the Declaration of Independence was a non-governing document and more of a statement of what was already apparent: that the war was not going to result in reconciliation between the two sides, and American victory would mean separation. Jefferson's prose in it is iconic in its usage of John Locke's natural rights principles and applying them to the current circumstances in 1776, but the dye was already cast, and the effort and work on the Declaration was the work of the entire Continental Congress and the specific committee (Jefferson, Adams, Franklin, Sherman, Livingston), not just Jefferson himself.
EDIT: And to parrot what some others are saying, I agree that there's basically a near-zero chance that Disney made this alteration because of a change.org petition. No company Disney's size pays attention to those outside of the most extreme circumstances. This was likely a long-time in the making internal decision, but the announcement likely got bumped up a little sooner given current circumstances. To think it's more than that is really grasping at conspiracy theory-laden straws.