Toutiao is a behemoth in the media space. Will see when it invades the US
It's very unlikely they'll be able to invade the US in a meaningful sense. Toutiao's primary business is media content aggregation. They're going to be incapable of presenting non-censored news, content, media. The CPC will require that anything they allow in their publishing space globally, be controlled and censored strictly to present the views of the CPC. What China allows their domestic companies to do internationally when it comes to media, is not very different from what they allow domestically. That's why companies like Baidu and Tencent, which are drastically larger than Toutiao, have been entirely unable to crack the Western media markets. The restrictions Chinese companies face due to the strict authoritarian regime at home, is extremely different from what companies in eg Japan faced when they 'invaded' the US 30 years ago (such as Sony in music & movies).
It's why there will never be a Chinese Reddit conceptually. Free expression is illegal for all Chinese media companies, it leaves them at an extreme disadvantage when competing globally.
I would expect one of these companies will want to attempt what Sony did and accumulate a music business. The question will be how they can manage to align that with the media restrictions they have to live within. Maybe Toutiao is young enough to still dare to attempt it, I think the older, larger Chinese Internet companies long ago learned to avoid challenging the CPC's boundaries.
In a less restricted atmosphere, companies like Snapchat or Twitter would be prime take-over targets for some of the Chinese giants looking for international expansion. I think a company like Tencent might have acquired Twitter by now if they could operate the platform without censorship trouble.
When it comes to app, companies will be ready to compromise to get as much data as possible (available).