I can see that a category of questions that would potentially be very problematic would be questions along the lines of "Which is better, Blender or Maya?". Now, such a broadly general question such as this shouldn't be allowed for other reasons, but what if it's more along the lines of "How does Blender handle materials differently from Maya?" or "Which renders faster, Blender or Maya?"? Should such comparative questions be on-topic for this site or off-topic?
I think questions focusing on interactions between applications are fine like "How do I prevent texture corruption when exporting to application x's format?" are fine. I think comparing performance in general is a can of worms that should stay firmly closed.
Questions that do this should either
- relate to any interaction the two software have. (file formats they might share, how to efficiently import/export from either to the other etc.)
- ask if Feature X from from (other 3D modeling software) is available in Blender
- ask what similarities they might have OR
- ask if it is possible to perform a certain task in Blender (for people who use other 3D software and are interested in trying Blender)
What kind of questions should I not ask here?
Avoid asking questions that have nothing to do with Blender Stack Exchange. This is not a random discussion area, it's a place for improving our community and website together.