[VBprogrammer]

> Ignoring the part where an entire group of people seem to have forgotten that caravans exist

I don't think they forgot that they exist, just that they serve a significantly different niche.

A caravan (or travel trailer) is designed to be moved easily and regularly. Ideally with the smallest vehicle possible. This means they are built incredibly lightly, with at least a passing concern for aerodynamics.

Tiny houses aren't really designed to be moved often. They have generally have much more sturdily built and larger internal fixtures. They aren't particularly great on the road, often people hire a company to move them when they need to. But they are designed to be lived in full time.