That's reductionist to the point of absurdity. WeChat does far more than WhatsApp. I'd say it certainly started off aping others, but WeChat has now grown into a substantially more innovative platform.
It's all in the one app because there is the state in the background intervening to make it so. But dictatorships are not market validation.
You can see it in other ways as well - In the US people generally shop on the web, but in China people shop in an app and the web version is not as good.
I guess some might call WeChat payments and mini programs innovative, but they're not very impressive technically. Take mini programs, they are basically a web app hosted within WeChat. It's kinda cool, like Facebook apps were kinda cool, but neither holds a candle to the power of a real browser. So Facebook apps were kind of a fad and then we got bored and went back to the open web. But Chinese people can't do that. It's not that they can't have web browsers, it's that they don't have any web innovation. It's not surprising, the web is so locked down with license requirements to even put up a simple web site. And so there's no good hosting options, which in turn makes it more productive just to stay on WeChat and sell your wares though Alibaba.
For instance, I don't really see a need to have the same app do chat and payment (in fact, I'd prefer if they didn't).
What about WeChat is particularly innovative, other than just bundling a lot of different functionality into one big app?
You not seeing a need and them meeting one that clearly exists have nothing to do with each other.
> What about WeChat is particularly innovative, other than just bundling a lot of different functionality into one big app?
Making it actually work well enough for millions of people to use it. I can't think of anyone else who's succeeded at that and there are plenty that failed miserably to build that type of "kitchen sink" platform.
Tencent are a phenomenal company that deserve far more respect in the west. The Chinese market may be distinctive, but WeChat's dominance of the Chinese market has come through innovation, clever design and good engineering.