Generic Animation Rigs are smaller in Editor.log but produce larger AABs/APKs

Hi, so I'm building for Android and trying to get the AAB and APK size down. The game is currently using the Legacy Rig for all of the characters, and it is them character animations that are the largest assets in the build report of the editor log. I've switched the characters over to using Generic Rig and the build report shows a significant drop in "Complete Size" in the build report, however, the output AAB and APKs inside are around 7Mb larger. How can the build report show a significant drop in size but the AAB shows an increase in size?

Note: Legacy Rig is using "Keyframe Reduction and Compression" for the animation compression, and the Generic Rig is using "Optimal" for the animation compression.

Generic Rig Build Report:
https://gyazo.com/8b5c56170268b733e0af6009ba306344

Legacy Rig Build Report:
https://gyazo.com/63379d5385a00e6316f59218438c34ee