I think the lad may have a point. Ignoring the engine for a moment, the quadracycle class of vehicle sells in hundreds of thousands in France to a demographic that is largely rural and, frankly, late middle-aged to elderly. These vehicles, most of them petrol or diesel, provide cheap and cheerful local travel, and electric versions at comparable cost are an easier “upgrade” than trying to get people to trade in their 1000km range, motorway speed cars for something that costs twice as much and (at best) goes half as far. Even the running costs aren’t as low as the headline figure for EV’s the manufacturers give out, when you take into account the battery rental, or the cost of battery degradation if you buy yours outright.
The Twizy is obviously not trying to do that, but Renault took the more obvious course of targeting it at urban youth, whose travel needs are (potentially) also catered for by a lower speed short range vehicle. Unfortunately, young urbans aren’t driving as much as they did, and urban youth is better catered for by public transport anyway.
The younger son is also right - nerds should, indeed, be trendy. The young - young women in particular - are not stupid, and employability and salary prospects provide more attractive “plumage”.