Is the writing category slow at the moment?
Not for me, it’s actually increased, but I’m sure it depends on a lot of factors. I just glanced at your gigs and saw several negative reviews. Your responses to some of them were less than professional. That could affect your search rank. You might want to write to Customer Support and ask if there are limitations on your gig ranking.
No. But perhaps you should petition Fiverr for a polymath category, since you are clearly a gifted multi-disciplinarian?
Those reviews are probably keeping away buyers.