Agreed.
The Saudi's are the principle lead and they responsible for their own actions in this region. This is supported by the five other GCC states, along with Egypt, Sudan, Morocco & Senegal.
My point is this is primarily an Arab-led coalition, with the US limited to providing intelligence and the ongoing policy of drone strikes on AQAP targets only.
Countries within the coalition maybe allies to the US, but I think linking the words 'US allies' and 'committing war crimes intentionally on civilian targets' is a bit disingenuous to the context of this conflict.
I'm sure certain unreported war crimes are being committed by IRGC (Russian Allies) in the Yemeni region and the Assad govt in Syria for that matter..
Maybe I'm being a pedant..