Yes, but how would you know Meta doesn't have a copy of your encryption key (ex: when you sign up) and keeps a copy of your encrypted messages somewhere?
AFAIK your encryption key resides as whatsapp's data folder but since whatsapp is closed-source you can't guarantee that whatsapp gave the encryption key to Meta's server at some point when it was created; (or it was created on their servers and sent to your device.)
One would just assume the encryption key is made on your device and never sent to Meta and all the E2EE messages aren't kept on Meta's server after they are sent.
Again, Meta is a company that is profiting on targeted advetising and selling user data, how would whatsapp be a free service without any profit?
Also, Here's someone who saw their whatsapp chat used for targeted ads on them in case you have doubt.