It's important to understand the distinction between chimeric and mosaic viruses.

Baric makes Chimeras. CoV-2 in comparison to the other closely related viruses in nature, is a mosaic. Lots of little changes all over the genome, not big copy and pastes.

See here for more detail on that distinction: https://www.reddit.com/r/science/comments/gk6y95/-/fqpbagf