If McLaren will bring a new floor to COTA is not too risky? Last year, due to Sprint, Mercedes and Ferrari misjudged the floor wear and both cars of Lewis and Charles were disqualified from the race final standing. Theoretically is not possible to happen again this year due to regulation change and now the teams have the option to modify the cars between sprint and race quali, but a wrong setup for the new floor can bring some struggles for Sprint (both quali and race) and lack of trust in the car from the drivers going into race quali.
And another headache for McLaren will be if both cars will have the new floor on they will spit the drivers one with the new one and one with the old. And again conspiracy theories will rise nonmatter the outcome: it the new floor is not working as expected the "fans" will say that one driver was sacrificed by the Team. If is working that driver was favored. I wouldn't want to be in Andrea Stella's place now