John fox has always had the same opinion on the safeties.
yes we need physicality in the secondary. Without harris, our safeties won't be hitting players? I find that difficult to believe.
Run support is a lot easier to coach than coverage skills.
Actually Fox's opinion has changed about safeties. He used to beleive that they didn't really matter and you could get them later in the draft. Obviously he drafted both Godfrey and Martin higher in the draft than he has before. There is a demand for safeties in the cover 2 to be quick to the ball and hard hitters. Because the middle linebacker sits further back in the formation there are many times when the SS plays as close or closer to the line than the MLB. So we need a physical guy who can cover yet deliver a big hit.
As for run support being easier to coach than coverage skills, it isn't strictly about coaching but a mindset. You can coach all you want but Gamble isn't going to be physical nor were some cover guys like Deon Sanders, DeAngelo Hall and the list goes on. Guys who make great SS like to hit and want to mix it up. They think delivering a big hit is as important as breaking up a pass or even intercepting the ball. Sure you can teach technique but you need to teach desire and mindset which is either there or not.
From what I have seen Godfrey has that mindset to a point while I haven't seen it in Martin. But to be fair he only started a few games.