Sorry I though your point was that the real life cars (with maths and examples given) would get better fuel consumption than those in the game, which is why I pointed out the fuel multiplier.
If your point is that your not a fan of the multipliers and the race should just be 10 laps with 1x fuel and tyre wear, then that's a little different and I have a few thoughts on that.
There are some people (myself included) that like the various pit strategies that come into play in longer races. If no multipliers were used then the race would have to be 70 odd laps, which I doubt would be too popular. PD's answer to this is the multipliers.
The problem we have in my eyes is that the races aren't quite long enough to ever really justify a pit stop. The time lost pitting is far greater than the time lost driving conservatively to make tyres and fuel last the distance. There was a time when the balance in this was better, and certainly FIA races used to be longer and pit stops were much more common than they are now.
I hope PD can address this as I get that many are not a fan of driving conservatively for what feels like a relatively short race. Either adding a few more laps, or speeding up the actual pit stop could rectify this.