Believe me, I can understand the appeal, but you've now identified the plusses and minuses, again. I have said repeatedly, and will always say, that accessibility (regardless of exactly what type) is a workaround. You are substituting one sensory modality (audition, in the case of screen readers) for vision, and when doing so you have to make some choices about how to organize things that simply don't have to be made for the sensory modality the thing being accessed was originally aimed at. Shortcomings of one kind or another are inherent in this process, as no given sensory modality is 100% directly convertible to another in a way that's as freely and automatically accessible in the native one.
I can imagine using Word for PDF almost all of the time and double-checking when you suspect something may be missing, as that's as close as you're going to get using a conversion method from PDF, not originally generated by Word (which is most of them). The conversion itself is noted to be an imperfect process, usually one where formatting only is lost, though. I'd have to be given specific examples of PDFs where content loss is suspected and play with them myself to determine as best I can what has actually occurred. This isn't something easily, or accurately, described in the abstract.
Brian - Windows 10, 64-Bit, Version 21H1, Build 19043
It is better to be hated for what you are than to be loved for what you are not.
~ André Gide