They have fallen off your credit reports, but they will never fall off Amex's internal records. Amex may forgive, but they do not forget.

I'm not sure what the odds are of Amex giving you another chance. Time helps, and the odds are better if you defaulted on 3 or 4 figures of debt. 5 or 6 figures and the odds fall. Some people default on a really spectacular scale and don't get credit from Amex ever again.

You really have nothing to lose by applying; if you are blacklisted, Amex will deny your app without even pulling your credit.

The easiest cards, anecdotally, seem to be charge cards...then Delta Gold or Blue.