Basically, the exception states that it is not an infringement of copyright for an Internet service provider to communicate content protected by the Copyright Act.
In fact, the act gives certain exclusive rights to the author. Reproducing or communicating a protected work to the public could result in copyright infringement by the service provider. So an exception was created to ensure that the Internet service provider never infringes copyright. This exception applies even if—and this is a statistic I found interesting and that you will allow me to disclose, because I think you are aware of it—32% of Internet users have downloaded, read or consulted at least one music file that included illegal content. This figure comes from a survey conducted in November 2017 on online consumption of copyrighted content. This means that, on the Internet, at least 32% of Internet users have, at least once in the three months preceding the survey, read, consulted or downloaded an illegal file.
I cannot believe that Internet service providers are not aware of that. You therefore understand that the exception in section 31.1 makes sense when looking at those data, since it seems to prevent Internet service providers from being held liable under the Copyright Act. If that exception did not exist, it would be very possible, or at least possible—I must be careful—that an Internet service provider could be convicted of infringement of copyright.