Dating back to even before NVIDIA launched its GeForce RTX series, there were rumors that some of its next-generation cards (which are now current generation) would lack real-time ray tracing hardware, and carry the "GTX" moniker instead of RTX. We haven't seen that yet, though a fresh rumor suggests that more GTX cards are actually being developed.
Early speculation suggested NVIDIA might release a GeForce GTX 2060 model with the RT cores disabled. The logic behind the idea was that the lower end GPU wouldn't be have enough muscle to process real-time ray tracing effects even with the RT cores enabled, though that might not be the case. It now looks like there will be a GeForce RTX 2060 instead of a GTX model.
Even if a GeForce RTX 2060 card does emerge, however, it doesn't mean there won't be any future GTX parts. Chinese-language website Expreview reports that NVIDIA is readying a GeForce GTX 1160 Ti graphics card on a version of Turing (TU116) that doesn't offer any RT cores, as those would remain exclusive to the RTX series.
The folks at Videocardz heard it will actually be a GeForce GTX 1160 (non-Ti). Either way, rumor has it that NVIDIA will be splitting its future cards into two tiers—GeForce RTX 20xx and GeForce GTX 11xx. That's probably a smart approach, as it would be easier to distinguish at a glance which specific models are built for real-time ray tracing and which ones are not.
This also makes sense from a pricing perspective. Many users have scoffed at the high price of NVIDIA's GeForce RTX series, which starts at $499 (reference GeForce RTX 2070) and goes up to $1,199 (GeForce RTX 2080 Ti Founders Edition), and even higher for some custom models. And of course there's the Titan RTX at $2,499, but that shouldn't be on anyone's short list for strictly gaming anyway.
A GeForce GTX 11xx series would presumably cost less. For users who just want a performance bump and don't care about real-time ray tracing at the moment, this would give them a cheaper upgrade path to the latest GPU architecture.