Why in the world do you want to fill those gaps? There's no reason to do so.

And is this a custom home or a tract home where you don't own it until it's finished?

Consult with your builder and your local building official. The responsibility of filling those gaps may rest upon your builder's shoulders.

Any latex caulk will be fine.

Rather pointless though.

If energy savings is your goal, it will be infinitely more useful to have speced above Code R Value insulation, spray and batt, ZIP sheathing, XPS or EPS on the exterior walls.

You might want to see if those gaps are a real issue. I mean it always helps a bit but there are probably significantly bigger gaps that you aren't showing.

The general advice runs something like less than 1/4 inch - caulk; greater than 1/4 inch non-expanding foam.

If this is a typical tract cheapest insulation house, your largest issues are around ceiling fixtures to the vented attic. I think in most jurisdictions you get foam around windows/doors but certainly this is an area if you don't. Then the seams between sheathing are another. There are usually other things you can find that are signficant extrenally that get caulked rather poorly or not at all.

Climate matters how much these things are worth. Just look at posts - cpartist is in Florida and Worthy is from Canada - which explains some of the variety.

This would work but you need to buy a gun to attach it to. Hilti also makes a similar product but there guns are expensive.

I would use the spray foam made for around windows that doesn't expand much. I also believe that all gaps should be filled.

California insulators do this, certifies it & building inspector checks

A blower door test will give you info about leaks.

"Most new builds require a blower door test". Are you sure about that? Certainly it is region dependent and it isn't the case in NC. As far as I can tell, we use 2018 which was adopted in Jan 2019. Generally it is a 3 or 4 year update cycle so we are due but not sure if the pandemic, supply chain concerns and housing supply concerns may slow that down.

Either way - visual inspection OR test is what it says - visual inspection is presumably free where a blower door is definitely not. Which one do builders choose?

Air sealing is never perfect. In typical construction, you can always do better. Why would that be inappropriate? Unnecessary is certainly up to debate and partly dependent on your goals.

Just because a test is required or done doesn't mean it is the best it can be. Our code requires 5 ACH50 or better(again "OR visual"). Upgrade options are HERO at 4 and Energy star at 3 (in my region of NC). Does that somehow mean 2 is not even better? As you know, passive house standard is 0.6. No US jurisdiction is anywhere close to that.

(ACH50 is the typical way that air infiltration is measured by a blower door test - it is the number of air changes per hour at 50 pascals)

Blower door test are worthless and amazingly inaccurate. The government just wants them done so they get more money and increase the cost of the house to help make it more unaffordable.

It appears you have panelized wall construction, and this kind of gap is the result. You can use the foam as suggested, a small cost. Your builder's insulator may or may not do them, and the inspector may or may not notice. So good for you if your builder allows you to do it. However, you may want to make sure the exterior is closed up with WRB and siding, otherwise the foam will bulge outside and cause difficulty to the other trades.