Honestly curious: knowing what everyone knows, why would any person who is not of Chinese origin, use WeChat? What's the use case?
I'll use it to evict stuff from my head so I can concentrate on other things (a "oh yeah I'm running low on tomatoes" thought results in a message for me to go back to later).
Since the UI is in the style of a messaging program then it's really low friction to enter stuff, as opposed to a dedicated note taking application. It's UI is also so clean and of a design not seen anymore.
Its QR code scanner is really good as well.
It should be noted that I'm also using it to message other people on the platform, but half the time I switch to the application I'm not using it to communicate with other people.
Someone may criticize sending so much data to "scary China" but I'm aware of what data I send through the platforms that I use. You wouldn't send your company's private information to a random server, and there's no reason why any other non company sponsored platform should be trusted.
I'm not into discussing controversial topics so the most scandalous message I've ever sent probably revolved around defending an unpopular bubble tea shop. I have alternative contact means so it's not like I'm being restricted in what I talk about. There's a proper time and place for everything. (and in the west there's memes about landing on a list for viewing an edgy meme or source).