Well, when I got into the hobby, I did just want an RTR. Something simple to learn with and not too much money. So I guess I'd have to come down on the side of "instant gratification". Would I have gotten a kit if I'd had the option? Possibly. But I doubt it. I learned the ins and outs of the car as stuff broke and I replaced and upgraded them. Which is better: building first, driving later; or, driving now, learning as you go? Who's to say? Individual's choice. What's your motivation?
But yeah, it's sad we're having this contraction in the RC industry lately. Can't say that I helped any. After the Evader got discontinued after a very long run, I moved on to 4wd platforms, and bought a HoBao (Ofna at the time) Hyper TT truggy. Liked it so much, I bought a couple of Hyper SCT trucks, used, from another forum member. The TT and the SCT share a majority of their parts, so easy to maintain. I haven't really bought anything new since.
Well, that's not true. I did buy a Traxxas Ford GT when it first came out. Just cuz I love the GT and a running model of one.... I just had to have. I don't really run it much, it's a shelf queen.
Traxxas is the 300lb gorilla of RC. They have managed to adapt with the market, plus, produce a wide variety of RC products from street cars to off road bashers, funny cars to boats, and even drones. So I think their position in RC is secure. They're their own entity, not owned by another outfit like Horizon or Great Planes.
Afaik. Tamiya will always be around too, I think. They are still popular in Japan, but I think they are the only folks racing them anymore. And some of those are just novelty races, like racing a bunch of Wild Willies that almost exclusively drive in wheelie mode. Where Tamiya succeeds is in "rolling models". They make really detailed bodies for their RC cars and trucks.
Serious racers go for the 8th scale buggies, 2-and 4-wheel drive. And those are almost always kits. But those platforms go for $500 or more, and don't even include wheels or motor systems and servos.
If you're interested in where the RC industry is nowadays, pick up a copy of RC Car Action.
Scale and Trail is where the hobby seems to be going, or at least it's a segment still growing. These are rock crawlers, and a lot of the fun is making them look true to life, with scale accessories like interiors, driver figures, jacks and functional winches.