Okay but...
1. We're specifically discussing Fallout 4 and he didn't indicate otherwise.
2. I guess that is a possibility. It could potentially torpedo their own game and earn them the ire of the entire internet (again). It will be a tough business decision on someone's part.
3. DLC is just officially produced paid mods. My point stands. Paying for more content is normal and done all the time, where that content came from means nothing to most customers. I'd have gladly paid for falskaar and other mods like it for skyrim, and I did end up donating to their authors if they had a donations page.
You've entirely missed the context of the conversation.
1. This conversation stopped being exclusively about Fallout 4's relationship to mods a couple of pages ago (about right after the link to the interview was posted for the first time) and moved onto paid mods and their effects on the industry, the customers and the modding scene itself.
2. It is a legitimate (if extreme) concern given the flabberghastingly stupid decisions the games industry seems to make on a regular basis. I personally think it's unlikely to come to pass, but I do not put it beyond them.
3. You misunderstand the difference between DLC and mods. DLC is produced by an official team whose members are paid to do it and who make it as either an extension of their vision or a quick way to snag some bucks for minor additions. Mods have traditionally been made by enthusiasts for free, for their own personal enjoyment of the game without expecting any financial reimbursement apart from fan donations. While this may seem like a minor difference, it is actually a huge one as it deeply affects the mindset of the developer and consequently, the final product. And thence stems the issue at the center of the paid mods debate.