Yes, there is flexible caulk.

That is what I also used since it's a perfect color match to Fusion Pro grout. I have never had anything crack, not in any color that I have used. It is flexible and remains softer than grout. Ha, I even have the same white herringbone backsplash!

@functionthenlook is there a specific one that I should get?

@lucky998877 I also used Fusion Pro grout for our tile :) It cracks the most on the longer quartz areas, which is also near large windows. We live in Seattle, so temps will be change from 30 degrees in the winter up into the 90's by the summer.

CD there are several different brands of flexible caulk you can buy. You will probably need to remove the existing caulk so you have a uniform caulk job.

Is the old caulk being removed, the area scrubbed with denatured alcohol, and new caulk applied? Or are they judt kinda halfwaying it?

CD, I live in a dry climate that goes from 10-100...maybe there is some other issue? Hope you' find an answer :)

That sanded grout-matching caulk is probably latex junk; I've never had any luck with it. Get some color matched 100% silicone please.

Custom does make a silicone grout that matches the fusion pro. That might be better. I noticed it on the shelf when I was at HD one day. But proper prep of cleaning out the old grout and thoroughly cleaning is always your first step. Also, the grout line needs to filled fully.

@User I've only seen them cut with a razer, then reapply. How much of the old caulk is supposed to be removed?

Any tips on how to properly remove and prep before reapplying new caulk?

Goo gone removes caulking. Use a brush to brush it on to caulk and let sit for a couple hours. Works fine for tubs and tiles. Not sure how goo gone would be on countertop materials. Maybe tape it out to limit contact with the countertop?

"How much of the old caulk is supposed to be removed?"

Every last bit.