I wonder if any of the muppets at mission control have ever bothered to think about it. Indeed, would they all even understand the question?
If you took off at TOPL weight AND used Maximum thrust AND had an engine failure around your wet V1 AND continued the take off - then your screen height would be 15 feet. How many times a year does that ever happen? (I have hardly ever had to use full thrust ever since leaving the TriStar)
On 99% of occasions we have used FLEX (assumed thrust) when the OAT has been lower than assumed and have therefore had a performance advantage due to the effect of True Airspeed. see:
https://flightsafety.org/asw-article/when-less-is-more/"
On the occasions when you use FLEX there will be more clearance than you fear.