Wd-40 is not a miracle product. It’s main purpose is to unseize stuck parts. It’s good to remove rust and moisture. It’s a mix of different chemicals, that does leave behind a thin layer of lubrication and does do some degreasing, but it doesn’t really count as proper lubrication (AFAIK it doesn’t last long, it’s too thin to be suitable for mecanisms that require heavy grease and attracts too much crap for mecanisms that require light grease)
Now I’m not the expert on bikes, I wouldn’t mind using it on my bike as part of the cleaning process but I’d only use it as a temporary solution for lubrication while I get the proper product.
I know, but she also works at Meta, not sure what you would expect.