Over the years there has been much discussion and debate about what career a GIS professional should aspire to, or what a GIS career even is. In my opinion you need to have at least one skill that nobody else has. I once called this the “geomatics striptease” — what expertise and value is there exclusively to us geospatial folks? I came to the conclusion that, if I had to strip off my non-exclusive layers, my naked self would be a geodesist and cartographer. No other field does these things, or at least not as well.
There may be a few other exclusive skills in GIS or geomatics, but many so-called geospatial expertise areas also reside in other professions. They’re not unique and this can be a danger area for career development — unless of course you want to become a multi-disciplinary generalist. In which case, sure thing, go ahead and become that ‘architect’ who orchestrates input from different fields. But whatever you do, it needs to be a conscious decision, and it requires focus. If you dilute yourself too much as a professional you’ll become the Swiss army knife that people only use when there’s nothing better at hand.
So to stay relevant, build a unique skill, stay focused, and never grow up. If you do those things, nobody can eat your lunch.