Vastly different engines
DA2 was done by Bioware, DAI is done by DICE which while belonging to EA as well is done by a different set of people. And frostbyte is done with a paranoid concern for secrecy, everything is compressed encrypted, checksummed and bit shifted after it is "done" Changing stuff after it is saved is hard for us modders but wouldn't be easy for DICE either.
Also the article doesn't mention but most of their devs moved to the Mass Effect 4 team after DAI was released so they must be lacking knowledgeable people
Yeah, same difference to a good developer. What I meant is: they know how to go about such things. And they did it before, so the thought will have crossed their minds that players will want to have such a DLC again. You develop with this thought in mind.
They will not have to put up with most security mechanisms because they have direct access to their code and they already have all the functions for creation finished (which, as I assume, are already build in a way to allow for repeated modification).
As for the specific engine, yes, I do not know its code. But they get the editor working at the beginning of the game. Cannot be so difficult to simply do the same thing again. The only problem should be getting the model back into it instead of only loading the templates.
BioWare is a huge company with about 1000 employees, and a part of EA even. I refuse to believe that they did not consider and plan for this prior to release. I really believe they got some very good people there, in all departments. I don't even want to consider they could be that short-sighted. Modding is a whole different issue than working on your own code.
However, this is really off-topic, so I'll leave it at that. And maybe you are right and they did not prepare for this. If you like to explain more about it, please just send me a PM.