The death of the perpetually tardy Model 3 may ultimately have less to do with it being an overpriced electric car than with something even more lethal to its chances . . .

It's a too-small sedan.

Electric or not, they aren't selling. Even the Toyota Camry and Honda Accord – both of them just redesigned – are experiencing sales dips. If these formerly perennial hot-sellers are in trouble, it's a clue that something is seriously awry with this kind of car rather than any particular car.

Others are spiraling toward the ground at freefall speed, like a plane with both wings shot off. Ford, as most everyone has heard, is going to stop making sedans – period. Death warrants have been signed for the Taurus and Fusion. Cadillac just cancelled the unloved ATS. The Chevy Impala will soon sleep with the fishes.

The why is easy enough to understand. Most new sedans are too small – for people and for cargo.

Especially mid-size sedans in the family car price range like the Camry, Accord and its various rivals. Consider the specifications of the Camry in relation to the crossover SUV it's related to, the RAV4.

The Camry is 192.7 inches long overall vs. 183.5 inches for the RAV4 – but the Camry is less roomy inside, particularly for cargo. It has a comparatively measly 15.6 cubic foot trunk with limited access vs. 38.4 cubic feet of space behind the RAV4's second row, which can be folded flat to expand that space to 73.4 cubic feet. Whip out your calculator and do some quick division. The RAV4 has almost five times the cargo space than the much longer (and so less easy to park) Camry's got.

This is a big deal for families who need space – and appreciate the versatility.

The RAV and other crossovers have something else the Camry hasn't got: The option to buy all-wheel-drive. This feature is available with almost every crossover on the market – even the low-cost models. But very few sedans in the family car class/price range even offer it.