Most views of the 19th century, at least from the point of furniture design, are of an era of ponderous, over upholstered furniture, dominated by revival styles spanning the 17th and 18th centuries. But the 19th century is really known for great industrial design, think of the work of Isambard Kingdom Brunel, for example. The furniture industry was no longer the dynamo moving the economy of England and this is reflected in its furniture design.
The great innovation of the 19th century, aside from the industrial dynamism, was in the large scale expositions that were mounted such as the Great Exhibition in 1851 at the Crystal Palace in London, a building created in nine months for the purpose of promoting the industry and crafts of a nation. By all accounts, the machinery and inventions shown were extraordinary. Furniture design was not uplifted by the event, however, despite new technology that certainly affected other crafts such as glass and ceramics.
Originality was sparked, however, by the work of William Morris who inspired designers in what would be called the Arts and Crafts Movement. These designers were clearly not in the tradition of 18th century maker/designers. Their furniture, think of the work of Arthur Mackmurdo or Charles Rennie Mackintosh or C.F.A. Voysey, was made with British materials and eschewed traditional forms, proportions and decoration.
The difference, at least from my point of view, between the eclat of the 18th and 20th centuries in furniture design is largely an intellectual one. Eighteenth century furniture is a continuum built on function, beautiful materials, astounding craftsmanship and wonderful design. This furniture was certainly status conscious. Twentieth century furniture is an intellectual pursuit aiming at comfort, functionality and originality, a status consciousness of originality. The seeds of it all were in that maligned era known as the 19th century.