Working as a consultant, there’s no guarantee that you’ll work with the same flavour of Linux all the time. This shop might be Ubuntu, the next shop Red Hat… The LPIC certifications require, and evidence, competency with Red Hat and Debian families of Linux. If you have to wear many Linux hats and they’re not all Red, get LPIC-2 certified.
Having worked hard and studied for some time I successfully completed my LPIC 3 cert, it is one of the top certs I have and it confirms to end clients that I have a deep understanding and complete end to end view of any Linux environment. The goal for any professional Linux specialist should be the LPIC 3 cert, I know from personal experience that it will not only benefit you professionally but also financially as end clients pay a premium for top rated quals and professionals who attain them.