No, it is not. For one, it's a corpus of read speech, which means it does not capture well the characteristics of conversational human speech – hesitation, disfluencies, different tones and registers, etc. LibriSpeech has a paper explaining the design of the corpus, all you need to read is the first sentence of the abstract to know what it is supposed to capture:

This paper introduces a new corpus of read English speech, suitable for training and evaluating speech recognition systems.

http://www.danielpovey.com/files/2015_icassp_librispeech.pdf

That sentence alone does not establish that read speech differs from conversational speech, thanks for the information / pointing this out, though.