I’ve never understood the whole Joaquin Phoenix thing. He’s just not my cup of tea.
And I saw a clip of the Battle of Austerlitz and it had laughable CGI, a battle that felt like a video game (if the general mutters “Charge”, the horsemen half a mile away spring into action) and it also seemed to focus on highly questionable action involving troops drowning in a frozen river thanks to well-placed artillery shots shattering the ice. The whole thing seemed like garbage to me.
Ridley Scott confirmed the only CGI used in the battle scene was the cannon balls being seen hitting the ice.
In real life, Napoleon repositioned guns to fire upon Russian and Austrian units which were escaping across one or two small lakes.