Your
Wax Plant (Hoya carnosa) plant looks good, a bit dusty but that can be remedied by wiping the leaves with a wet paper towel, or giving it a gentle shower. Dust buildup on the leaves deters light penetration and the plant's ability to photosynthesize.
You can expect active new growth to begin with warmer weather in the summer months. My Hoyas have just recently begin to take off because here in Florida, we've been spring temperatures ranging in the mid and upper 80's! Plants (even indoor plants) usually rest during autumn and winter and growth slows down until warmer temperatures return.
I can't see the soil in your photos but regarding your comments
"I rarely water it because it isn't doing anything. Indoor plants require less water in the winter months when they aren't actively growing but the soil should never be allowed to totally dry out.
It sounds like you have a handle on your Hoya plant and I hope you will share more photos in the coming months!