To directly answer your OP question - I 3rd or 4th the GP5000. I ride the GP5000 (and have ridden many alternatives) - I don't race.
My kid did his 1st try this year in TX 2-3 months ago with about 500 competitors. He got the fastest bike time.
He went with the same ITT philosophy - If going for the win on a one-day event, use the fastest (everything) knowing there is an increased RISK of not achieving due to a mechanical.
Vs using more durable (GP5000), and guaranteed slower time.
Of course, the above depends on where you are expecting to place and what matters.
If you are totally expecting to dominate, or be beaten, a 3-4 place swing doesn't matter, just training, got no ride home/support - use the slower (GP5000) stuff. The GP5000 is still a fast tire.