Can you share some examples of the outdated information and the lack of understanding by the authors, so we may all learn? From a quick skim I noticed the article mentions CopperheadOS, even though it was renamed to GrapheneOS in 2019, so I'm inclined to believe there are more outdated pieces of information. But again, highlighting the misleading fragments would be an even more valuable comment.
You won't be able to run banking software or play DRM content this way, but I think WhatsApp and Signal should work. I can imagine some features not working (video calling, cloud backups) but basic chat should work.
Sibling mentioned Waydroid, but I've been using Matrix and bridges.
This means there's only a single app that needs to find updates to messages - a major boon on de-Googled Android too. Everything's in one place, from Whatsapp to Discord to Telegram. Best of all, there's a variety of clients for Matrix. Telegram, Whatsapp, and Signal have desktop applications for Linux, but they're lukewarm at best - some have scaling issues due to screen size, some are objectively not meant to be used standalone.
Matrix bridges are pretty cool. And I hope they are never blocked.
But unfortunately they don't support audio or video calling for Whatsap [1] or Signal. That is a critical feature. I doubt anything short of legislation would force Whatsapp or Signal to allow this feature.
Sent from my PinePhone Pro.