I have a rather different view, as the change happened soon after the Fire phone debacle, Bezos's pet project. Seemed like the bigger investors were getting nervous about him, and moved him to a more honorary position.
In any case, the only long-term contracts I've ever seen for any AWS product is the long-term discounts for servers. Everything else seems to be hourly (or by the millisecond for Lambda, but I've yet to find a use for that). Pretty much the opposite of Oracle.