Yeah, they've been having issues with their new movies being profitable. The last two, Marnie and Kaguya were flops in terms of money even if they were reviewed well (both cost in the area between 40 and 50 million USD). They went over schedule and budget, and it was a complete mess.
When Miyazaki left, it might as well have been over. Supposedly they'll remain as a shell company to keep their rights on their films and that's it. The Ghibli Twitter seems to indicate that they're not totally going away but that they are taking a break to consider the future of the company.
However...
Source: The Kingdom of Dreams and Madness, a documentary about Ghibli.