Chris Webb lays out an explanation:
I’ve been working with Microsoft BI tools for 28 years now and for all that time Microsoft has been consistent in its belief that semantic models are a good thing. Fashions have changed and at different times the wider BI industry has agreed and disagreed with this belief; right now, semantic models are cool again because everyone has realised how important they are for AI. As a result, some of Microsoft’s partners and competitors (and sometimes it’s not clear which is which) have invested in building their own semantic models and/or metrics stores, some of which don’t work at all with Power BI and some of which only work with significant limitations. This naturally raises the question of whether Power BI will ever work properly with them. The answer is no, and in this blog post I’ll explain why.
Read on for Chris’s explanation.