How to change margin or padding in columns header

Might want to submit this as a feature request here: https://community.airtable.com/p/product-ideas 

As a workaround, you could try using Userscripts to try to get around this?  I poked at this for a bit and found that the empty space  contains the dropdown arrow that shows up on hover but couldn’t figure out where the minimum width was coming from I’m afraid