The decision to leave mainland China occurred in 2010 after Google announced that, in response to a Chinese-originated hacking attack on them and other US tech companies, they were no longer willing to censor searches in China and would pull out of the country completely if necessary. [0]
What's not well known is that Google still operates in China and makes billions [0] off advertising there. So Google has hardly 'pulled out of China' despite not running a search engine. At this point, they wouldn't succeed even if they tried - so it's more an excuse than anything else that they don't _want_ to operate Google the search engine there.
[0] https://www.theinformation.com/articles/googles-ad-sales-fro...
The Information article you cite, explicitly says itself that this increased revenue comes from "a wave of Chinese tech companies buying ads outside China to promote products like the TikTok video app and the Alipay mobile wallet".
Are you trying to imply that the actions of any Chinese company should be assumed to be an extension of the central government's? I mean, I suppose you could argue that. But otherwise, all this represents is a company with an international presence buying ads to advertise their product/service.
Google has always been a B2B company - their revenue comes from businesses. Even if Google the search engine were running in China, where would the revenue be coming from? Still Chinese businesses. I don't think it's relevant whether the spending is domestic or international in nature.
Again, it's totally fine if you want to argue that as I agree there's some merit to the idea, but from your first sentence, it seems like that isn't what you're trying to say.
Fun anecdote: In 2010, it was Sergey Brin (now a president of Alphabet) who drove Google's withdrawal from China. In 2018, in what I'm sure is just a coincidence, the public found out that Google's project shares the name with Brin's yacht: Dragonfly.