Using "style" on word to allow alt text or decorative mark on it

Good morning,

I'm a digital accessibility expert, and I use a "feature" in PowerPoint that allows me to add alt text to a syntax or word when generating the PDF format.

I just need to use the "style" option (format shape / solid line for exemple) on a word for PowerPoint to see it as an object, that way alt text or "mark it as decorative" will work fine.

My question is, is this process intentional or am I using a bug (eventually fixed in the future) to make the documents accessible?