I think it's because the one value that the Pats really have is seeking value. For years, the league at large overvalued high draft picks and high-priced veterans, so the Pats traded in mid-tier veterans and mid-round draft picks. They still do, based on their roster construction. But as the league starts imitating, the market dynamic changes. Other teams are starting to come around to the Patriots' way of doing things, and as they we may see the Pats be among the first to flip the other way if the balance shifts. Because the Pats don't inherently care more about mid-tier veterans and 2nd-5th round picks; that's just where the value has been. But if they currently feel like Brandin Cooks gives more value than the #32 pick, then they'll make that trade with no real regard for its consistency with past trends, because value is their only real metric that they care about.
We've seen shifts before with the Patriots, specifically re: their front seven. We ran a two-gap 3-4 for years because only a couple teams wanted guys that fit that skill profile, so we could reliably get the very best of them, and long term we couple keep them by paying them less than their overall contribution would otherwise dictate. But as soon as a bunch of other teams like Cleveland, KC, NYJ, Miami, etc. adopted their own versions of 3-4 defenses (in large part because people were hiring Patriots' staff left and right), the Pats zagged back to a defense that shared many of the basic elements of what they'd run before, but was more closely aligned with a 4-3, since supply and demand now dictated that there was greater value there.
Similarly, right now the Pats use a bunch of undersized, quick, agile receivers. But it's not because those guys are actually better, it's because the rest of the league fails to see the value in them, and therefore we can get a lot of player for not a lot of price. If the pendulum ever swings the other way, and the market catches up to the production, don't be surprised to see the Pats start going after big, tall, physical jump-ball receivers instead.
The same basic principle can be seen anywhere, in different sports or even outside of sports. Billy Beane and the Oakland A's is another great example. For years, everyone associated Moneyball/Billyball with high-OBP hitters and sluggers who could clear the bases, but it was never really about that. That's just where the value was, it had an outsized correlation with success for how little the league valued it. Once all the big-market teams (like Boston) started hiring moneyball disciples who went after the same things, it stopped being an exploitable market inefficiency, and actually became overvalued instead. So the A's zagged when everyone else was zigging, and spent the next few years trafficking in mid-grade starting pitchers and unusually good defenders. Like Belichick, Beane didn't have a model for what his team needed to be, in the traditional sense. His only model was that he'd see what everyone else valued the least, and build a winning program using an awful lot of that.