This product is amazing and a must-have for all Quest 2 owners.
It doesn't affect the tracking capabilities, it is lightweight and also mingles with the controller design.
However, it could be included in the grips package. It is indeed included in the version for larger hands, but not for the improved regular sized one.
If you add this product with the grips, it will be already more expensive than the larger hands version (that includes it). Therefore this is something that could be changed: KIWI should add other items to the package and increase the price a bit.
Long story short, buy this product if you are already happy with your controller accessories.
If you have large hands, I'd suggest getting the grips that include this item, as it's a better value for money.