To some degree, this is a consequence of the nature of the field you're working in:
* if the physics is so completely understood that you can confidently predict something will work from your sofa, and give an error-free recipe to build it, you indeed can invent from theory... but how deep can this invention be if the problems of the field are completely solved?
* if you are working in a field at the edge of human understanding, you cannot have the confidence in your ideas without having tested them experimentally; a theoretician makes at most a minor contribution to the actual inventions being realized, because he's producing - most likely somewhat wrong - hypotheses.
This latter kind of "theoretical" inventions are heavily subject to survivorship bias. Fifteen competent theoreticians make different predictions - all according to best, though incomplete, model of the world; a successful experiment validates exactly one of them, and we end up exalting the lucky winner as the "inventor".
In practice, any unexplored corner of the field will contain surprises; these will require extra theoretical development to cover.
Usually things like imperfect understanding of materials get in the way. Pretty much the reason you need both theory and experiment to make progress in every single area of matter-based technology (i.e. not software).
* if the physics is so completely understood that you can confidently predict something will work from your sofa, and give an error-free recipe to build it, you indeed can invent from theory... but how deep can this invention be if the problems of the field are completely solved?
* if you are working in a field at the edge of human understanding, you cannot have the confidence in your ideas without having tested them experimentally; a theoretician makes at most a minor contribution to the actual inventions being realized, because he's producing - most likely somewhat wrong - hypotheses.
This latter kind of "theoretical" inventions are heavily subject to survivorship bias. Fifteen competent theoreticians make different predictions - all according to best, though incomplete, model of the world; a successful experiment validates exactly one of them, and we end up exalting the lucky winner as the "inventor".