BMW do still make an inline six of 1.6 litres - in their K 1600 motorcycle.

It's not for me (I prefer twins, hence my username), but has some fans.

Benelli & Honda have made inline-6 engines for motorcycles in the past (and Kawasaki?). Sukuzi did consider a V6 1 litre for their GSX-R, I think while superbike racing still used a limit of 750cc for 4 cylinder bikes (so the 1 litre bikes were generally road-use only).

I do like inline-6 car engines, especially in Triumph or BMW small capacity units. I'd prefer an inline-4 over a V6 for small capacity units. A 2-litre V6 based on Ford's current 1-litre 3 pot would be very interesting.

Do smaller V6 engine's loose torque the smaller they are scaled ?

Maybe this is why these are not made in smaller capacities

They don't loose torque but it tends to be higher up the rev range compared to a 4. With bigger engines this is not much of an issue.

Take 2 1.8 litre engines from the early 90's that were sold in the UK market in "sporty" cars, the Mazda MX3 and the Ford Fiesta RS1800.

Mazda 1.8 V6 130 PS @ 6500 and 115 lbs/ft @ 4500

Fords 1.8 DOHC Zetec 130 PS @ 6250 amd 120 lbs ft @ 4500

In reality absolutely sod all in it but the Mazda would be way more expensive to make.