There are more people that just bash their cars/trucks than race. And for them, tuning an engine maybe difficult for them. EFI would reduce tuning to the point that newbies could just run their nitro vehicles just like an electric. Your reasoning about increasing performance just wears out the car makes no sense to me at all. The very nature of ALL motorsport racing is to win races.
The number one way to win a race is to be faster than anyone else you race against. The number one way to be faster is to have as much horsepower as you are able to legally run. EVERY year, a new engine will come out that will have more hp than last year and yes your car will wear out faster because of this. Like everything else in life, if YOU do not want that product, dont but it. But if people can race within THEIR budget and beat you with a better engine...don't complain. An electric car is WAY easier and cheaper to run than a nitro but a nitro runs more like a real car which everyone likes. It took me over a month to tune and break in my NovaRossi rr12l3. Overpriced? YES. Too much power? YES...
Trade it in for a cheaper, lower performance electric? HELL NO...
Running nitro is damn expensive and gets more expensive every year. But...I want the best nitro car I can afford...