I've been watching my neighborhood birds for a while now and they indeed have individual personalities. It's pretty cool to know for example when a neighborhood cat is approaching, how it's approaching (stalking or walking?), and even which cat it is all because the birds communicate it to each other.
If you're interested in diving deeper into this bird world, I'd recommend starting with "What the Robin Knows" by Jon Young https://www.amazon.com/What-Robin-Knows-Secrets-Natural/dp/0...
Jon still does a lot of programs and workshops and research and it can be a fascinating rabbit hole to dive into.