Experience orbs rise slower than other entities in bubble columns. I am unsure if this is intended, because they fall in the same speed as items in downwards bubble columns.
This also happens in Bedrock Edition and is considered a bug (MCPE-106439), which was introduced in the Nether Update.
1. Create the setup shown in the video.
- Build two upwards bubble columns of identical height.
- Set two tripwire hooks and a tripwire above each of them, with a redstone lamp.
2. Set two command blocks to summon an item and an experience orb in each of the bubble columns simultaneously.
The item will trigger the tripwire much faster than the orb.
Experience orbs should float in the same speed as other entities in bubble columns.