I've done the same thing with less than $700 worth of camera and lens. These results have nothing to do with the camera she is using.

I did with my dogs with a Sony A6k and old minolta 135 2.8. Sub$800. It’s about shallow depth of field, some bokeh balls, and knowing how to control the light. Yes she prolly tweaked skintone in post, but she mastered depth of field and a longer lens (like art lenses) with wide aperture are the kind of tool to get the effect

yeah, but you can achieve the same with a cheaper model (though the full frame sensor of the 5d helps). And you can get cheap old lenses with the same aperture if you don't mind manual focus. Basically to get all those out of focus lights (bokeh) you need to place them in the areas that is not in focus. Usually the cheaper the camera, the smaller the sensor and the bigger the in focus area, so you just need to get those lights even closer to your lens. Longer lenses (telephoto) will also have a shorter focus area but you just need to get much further away from the subject. So it's doable on the cheap, just way easier with a 1.4 85mm lens on a full frame camera.