A lot of the older Keanu isn't CG, it's filmed. They switch to the CG versions later. This confused me a lot as well, as I was totally blown away with the first Keanu I saw.
"Even now people are confused, having watched the footage several times. “The first time you see the older Keanu that was a video shoot that we (Epic) filmed of him,” Pete explains. “After they come back after Morpheus that was all the CG versions. It was color corrected to match and look the same.” There is also one point where we see footage in the mirror this was real film footage that was comped in UE5. The first shot of Morpheus is also not CG, but then becomes CG when the young Thomas Anderson (Neo) appears. Even the desk scene at the beginning when Anderson is asleep was a real-time recreation of a scene from the original film."
"Even now people are confused, having watched the footage several times. “The first time you see the older Keanu that was a video shoot that we (Epic) filmed of him,” Pete explains. “After they come back after Morpheus that was all the CG versions. It was color corrected to match and look the same.” There is also one point where we see footage in the mirror this was real film footage that was comped in UE5. The first shot of Morpheus is also not CG, but then becomes CG when the young Thomas Anderson (Neo) appears. Even the desk scene at the beginning when Anderson is asleep was a real-time recreation of a scene from the original film."