There's two separate things at play here.
One is "I don't want to use Meta products as a matter of principle", and WhatsApp's a no-go if that's your posture.
The other is "I don't want to drown in horrible, algorithm-curated junk content". Instagram is just as bad as Facebook there, but WhatsApp is definitely not the same.
100%. Whatsapp is still zuck, but it doesn't have a "feed" and that's the most important thing about it for me.
Now at the bottom it has a few tabs: Chats, Updates, ...
Updates are broadcasted, but they disappear after 24 hours.
Step 1) Keep updates for a week, later forever
Step 2) Mix Chats and Updates
Step 3) Add a few relevant patrocinated posts
Step 4) Change the css from green to blue
Step 5) Profit