Playing devil's advocate here: Given that there is not a shred of evidence that we have found so far that supports the idea of the existence of the Proto-Indo-European language, why are so many linguists (and researchers from other disciplines) continuing to invest in research with a firm belief/assumption that PIE ever existed? Is it because it would be a career ending move for a linguist to conduct research that as…
Details of PIE are subject to revision based on new evidence. Its existence is not in question.