Unity aab not compliant with the Google Play 64-bit requirement
It looks that there was a bug in the Play Console where this message was displayed even when the AAB was compliant. This should have been fixed last Friday afternoon. Try again now.
For those who have this problem since yesterday (August 19, 2019):
In Player Settings > Other Settings you must now uncheck the x86 box (It is for the 32-bit Intel architecture).
You will now only have the following warning:
The device types on which your application can be installed will be more restricted.
But, in my case, it drops from 12392 devices to 12385 devices.
Here is the opinion of a Unity member on the issue:
x86 is used by less than 0.4% of all Android devices, so it shouldn't have any real impact.
x86 target will be removed completely in Unity 2019.3.