I don't believe that at all. Even ignoring the fact where I almost never believe that about DLC (Witcher 3's "free" post-release mini-DLCs, do feel like they fall in that category. Except for the resell part. Instead of putting them out to generate money, they put them out to generate good will & press.)
Given how large a part of the base game the settlement system is, I was fully expecting a "settlement additions" DLC, even before they were announced. (I also love the contrast between all the "OMG, this DLC just added some more _______, which I'm not interested in! They shouldn't do small DLC like this!" threads, and the various "We need a small DLC like Gun Runners Arsenal, which just adds some more guns!" threads.)
Honestly, I don't understand the OP's "horse armor" comment, given that this seems more along the lines of Hearthfire. Which never got the whole "ew, horse armor!" criticism.
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Honestly, I'm tired of Horse Armor being a millstone around Beth's neck. It was the dawn of DLC, no-one knew how/what to do it yet, so they tried all sorts of stuff to see what worked and what didn't. It was a new experiment. So yeah, they ended up with duds like Horse Armor. But that's years and years ago now. Let it go.