Upgrades and EL access are NOT part of Diamond benefits (or Gold) UNLESS you chose them as your MyWay choice. If you don't chose upgrades, you can't expect to receive one. If you want guaranteed EL and breakfast, you MUST have the upgrade choice in MyWay.

I have MyWay set for upgrades when traveling ex-US. I have always gotten an upgrade and EL access (if available). The London Waldorf is one of the sticklers for the MyWay choice.
As Gold I got an upgrade to a regular Executive room. As Diamond, Executive rooms but I did get a suite twice. Not expected but very pleasantly surprised.

Make sure your MyWay is set to Choice 1, upgades/EL access.