Security SWE here. I have worked with WhatsApp's security engineers, I donate hundreds to the Signal Foundation every year, and I like to think I have a good amount of experience by now in the security industry.
> you are a fool if you install WhatsApp [...] meta is balls deep inside the app and watching what you do.
WhatsApp uses the same protocols as Signal under the hood. The Signal team even helped WhatsApp implement it. Furthermore, the app has been extensively RE'd by third parties to validate it's doing what it says on the tin.
https://signal.org/blog/whatsapp-complete/
> When I hear friends talk about WhatsApp I cringe. The few who have signal I regard highly.
Your clear lack of knowledge on the subject matter combined with your judgement of others says far more about you than your friends. It seems that you have fallen victim to the Dunning-Kruger curve, so consider not judging people until that is rectified.