I don’t think that’s necessarily true. Some products will look out of date. Some won’t.

Here is a record player from 1956: http://www.flickr.com/photos/nickwade/4130988683/in/pool-464...

And a tape deck from 1975: http://www.flickr.com/photos/8944091@N08/2068062385/in/pool-...

The technology is obsolete but I don’t think the design is.