You favorite channel might have disappeared because the creator got bored and tired of doing it. Three kinds of videos seem to be popular in the nomad/travel genre. There is the vlog type where the creator is the content. Caravan Caroline, RVDebs, DebraJoy, Ashia of Pandamonium, and Mike of Living Free are that type. There is the destination type, like Adam the Woo and Burger Planet. And there is the information type, like Slim Potatohead and Cheaprvliving. Some creators do more than one type, like Nomadic Fanatic and Little House on the Road.
Few people are as creative as they think they are. Coming up with fresh ideas, day after day and week after week, is hard. Sooner or later, they all start repeating themselves and each other. The more you post, the faster that day comes. Everyone is going to Disney or down Rd 66. Everyone is emptying their tanks or doing a cooking show. Everyone is doing a tour of their, or someone else's, vehicle or complaining about their breaks or their transmission. Everyone has a "story" and is on a "journey." They make it sound like they are bloody Bilbo Baggins. Could some of them be any more pretentious?
Unless you have reached the point where you have a cult of personality going for you, where YOU are actually the content, people will get bored and stop watching you. You may still have the subs, but they won't click and watch. That personality thing is hard to predict. I don't mean to be snarky, but who would have thought Letty or Elvis or even Bob would get a devoted following? Most people just aren't that interesting. For the ones that make it work, it is golden.