BuddyPress.org

“get” filters don’t modify data on input/on save, which is when KSES is normally run.
Off-hand I don’t know which filter does this, I’d suggest looking through the top of the bp-xprofile-filters.php file and comment them out until you find the one that lets you do what you want.

Then hopefully you/we can modify that filter, somehow, once we know which one it is. You don’t want to remove KSES entirely, this is unsafe and will let people hack your site.