Keep doing festivals, that way the promotion is already there and a bigger audience outside of Janet fans will be exposed to her.
Forget about the expectation of traditional promo and album releases, it's a new time and we can speculate on what she should or could do forever, but she's proven herself to be a solid draw at festivals and it's a win win for everyone.
New music isn't going to guarantee seats sold. It would be nice, but doing festivals and residencies here and there also keeps her from having to do hundreds of shows. She's not going to keep doing major tours for the next ten years, she also needs time to enjoy life outside of work and raise her child.