I know this is likely something that has to get fixed on Lawnchair's side so I made a post on their Github already but I thought I would post it here too because I feel the issue is quite bizarre, no other launcher does this.
I tried five different launchers and they all work fine with KLCK, only Lawnchair stops it from ever showing up. As soon as I clear defaults KLCK comes back right away.
More details in the Github post: https://github.com/LawnchairLauncher/Lawnchair/issues/2030
I tested it with three different phones and two Android versions, all have the same behavior.