As we see more autonomous AI coding agents enter the market, do you think developers’ ability to collaborate with their peers could suffer? Do the pros outweigh the cons when it comes to replacing a human peer programmer with a virtual one?

There is too much business requirement or customer needs information that the engineers know about that an AI agent doesn't that means you can't replace an human peer with an AI peer for the reasons why you communicate with your peers. It's a tool, use it for "monkey work" that it's good for but don't expect to replace communicating with your peers with it.

Coding agents have been beneficial for tedious work that I believe often gets overlooked.
I've seen coding agents accelerate code review, bug fixes, upgrades, updates, etc..

This leaves MORE time for humans to pair up and engage in the more strategic and complex work.

To an extent, yes. However, we need to look at the bright side of things and see how this improves the ability to deliver quality code. 

The coding agents may never be able to replace humans in their entirety due to the lack of perfection and ability to look at the entire assignment as against just a given class.