Hello,
The Screaming Frog fails to start because it expects the PRETTY_NAME from /etc/os-release to be quoted, but it will not handle the case when it isn’t and it will fail.
To fix the issue, edit os-release file and add double quotes to PRETTY_NAME value:
sudoedit /usr/lib/os-release
....
PRETTY_NAME="EndeavourOS"
Anyway, you should report this bug to ScreamingFrog upstream.