Im sorry for this statement, but motorsport is never about saving fuel.
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Nonsense! Teams have always run as little fuel in their cars as they can possibly get away with, right from the very first races 100 years ago!
More fuel = more weight and therefore less performance. It's totally in their interest to run as little as possible.
Back in say the 50s and 60s, if you even had a fuel gauge - it wasn't particularly accurate. Plenty of teams got it wrong and the drivers run out of fuel before the end.
In the Turbo era, drivers were constantly managing fuel consumption. They could turn up the turbos and run faster, but if they did that for too long they'd run out of fuel. They spent the whole race managing their fuel. Again - if they didn't, they ran out short of the finish.
With refuelling, it was less of an issue because the stints were shorter, but I can assure you that the drivers would still be managing their fuel to eek out an extra lap to jump their rival in a pitstop.
Mclaren and Hamilton didn't manage their fuel as well as they could. Perhaps they took a gamble on the track staying wet longer than it did. They would have benefited massively from the lower fuel load at the start (not just the weight, but the car would be easier on the tyres). Had they run Lewis with more fuel he may well have been well behind before they even got to the stage where he needed to save fuel. Equally it may have been a stoke of genius had to worked out, and the extra performance he gained by carrying less fuel could have brought him the win.
I don't understand why you'd want to take element away from the sport. It would make things even more static as the teams would have no opportunties to gain an advantage over their rivals. Simply the faster cars would drive away gradually into the distance. Instead as it is currently, we see different performance levels at different stages of the race as different approaches play themselves out.
Everything about motorsport is about compromise - but compromise that gives you the ultimate performance. Fuel is one part of that. The drivers are still pushing the boundaries of what they have at their disposal - and that includes still lapping as quickly as humanly possible while managing their fuel. It's part of the skill required to be a racing driver.
I think on this matter you may only be seeing the trees