From what I understand, it is possible to perceive a dream to be many years, but you don't actually experience every moment of it.

LaBerge's experiment showed that dream time and real time are equivalent, not non-lucid dreams.

In non-lucid dreams, you can dream of abstracts and your subconcious will fill in the details. I think if you then dream of multiple sequential abstracts that follow a chronological order, it is possible that a dream may be perceived as lasting a long time.

I remember having non-lucid dreams that seemed like they lasted days, but never lucid dreams.