RV of Gifting - Benefits in delaying?

Curious what the consensus is on this.

Question 3.c of volume 3 reading 11 asks if there is any advantage in delaying the gift by five years?

My response, only advantage in delaying the gift is if the grandson’s tax rate is expected to increase or if the grandparents tax rate is expected to decrease. I find my response fair, and accurate - anyone think otherwise?

The text goes on to explain there is no benefit in waiting to gift the $1m now vs. 5-years as implied by the RV calc. I agree but also disagree, thoughts?

Nope it didn’t, good point