According my experience, always aim to become into a renaissance person. Or at the very least, into a quite curious generalist and happy jack of all trades. In my opinion, it always will be better approach life from many, multiple and different perspectives. Skills, expertises and specialties come and go all the time. Many of them turning out to be obsolete, dismissed or useless in a very short period of time within the society. Whether by the automation, disruptions in the job market or by the lightning fast changes that the current technology impose in human beings everyday these days.
Most of us were trained, indoctrinated and formed by the still current education system to be mere employees. To work for someone else and make them richers in the process until our retirement. Selling and exchanging our time and just a fraction of what we really know for an even lower fraction of the money that we could get if we could show and apply all of what we know and fully master. Most of us were educated for a world that doesn't exist anymore. A world whose education from an "Industrial Era" already has become clearly obsolete and useless by these days.
We all only have 24hrs a day available. So, we should fill our skillset pouch with as many different, varied, multiple and colorful marbles we can find in our life. So we can play a very joyful and highly fulfilling "marbles match" in any terrain we may step in. Yeah I know, too much yadda-yadda & blahblahblah in this comment. :D