This was raised by @Konfekt in #1883 (comment) and also discussed several years ago in #557. Since VimTeX v2.0, this should be relatively straightforward to implement.

Before I implement anything, I wanted to be sure I "understand" the feature. We want:

• \mathbf{text} to be displayed as simply text but bolded.
• \mathrm{text} to be displayed as text (not bold).

Is there anything more?