Is the "Data Mod" option for the Chronicle DLC officially disabled?

I am a devoted fan of the Age of Empire series and have been especially interested in playing the campaigns.
As regards AOE II, on which I spent thousands of hours over a decade, I always enjoy playing the campaigns by applying a data mod - mostly just for lifting the population cap and boosting the resources. As a seasoned user of the Advanced Genie Editor myself, I am always delighted at implementing a little customization here and there.
Recently I bought the Greece DLC and was looking forward to to playing the campaigns. However, upon entering the campaign interface, I am baffled by my inability to find the selection square for “Data Mod” (it’s normally to the right of the square for selecting campaign difficulty).
What’s going on? Is this the result of the developers’ decision of disabling the data mod option for the Chronicle’s campaigns?? I searched extensively on the subject and found NO announcement of such a change whatsoever. All AOE II’s campaigns allow for playing with data mod, including the standalone Return of Rome DLC - there is no reason for me to expect otherwise.
Could someone please enlighten me as to what the cause of the issue really is?? Is it really the case of the data mod option being intentionally disabled??