The CRTC is catching telemarketing violators and fining them.
The DNCL has been frequently criticised as ineffective and badly managed. Things have improved since it was first implemented though costs have gone up very significantly for subscribers.
Prosecutions do result for offenders. When the list was new the CRTC often gave out warnings to encourage compliance. These days you should not count on just getting a warning.
Some of the prosecutions and penalties are reported on the CRTC web site.