Hello there!
Is the situation with supporting GetFeatureInfo on WMS on ArcGIS Online still the same? Or did Esri change the opinion?
Thanks for any newer information.
Zdenek,
It has been said that getFeatureInfo / pop-ups are now supported in ArcGIS Online. I have not tested this. See the section titled 'Pop-ups in OGC WMS layers' of the article linked below.
What’s New with OGC Support in ArcGIS Online (June 2016) | ArcGIS Blog