Every so often, a GOP presidential candidate campaigns on replacing the Federal income tax with something else. Unfortunately, that hasn't caught on thus far.
In theory, there are two ways this could happen. One is to repeal the 16th amendment. However, that's a glacial process with dim prospects for success.
A far more efficient alternative is to simply defund the IRS. You don't even have to abolish the IRS–although that would be even better.
That alternative leaves the text of the Constitution intact, including the odious 16th amendment. But it would effectively nullify the 16th amendment. Without a corresponding collection agency, the 16th amendment is a dead letter.
And that's the strategy in Amoris Laetitia. Pope Francis didn't so much repeal Catholic dogma as defund Catholic dogma. It made official the informal nonenforcement policy that's already been in effect. The Pope needn't change dogma to change policy.
Everything may look the same on paper, so long as you don't pay too much attention to the new disclaimer–which effectively abrogates traditional dogma through studied neglect. It's striking how many pious Catholics are taken in by this ruse.