Is a knowledge panel the same as a Google Business Profile?
No. Google says Business Profiles "look similar to knowledge panels, but are specific to businesses that serve customers at a particular location or within a designated service area." A plumber, roofer or HVAC company that serves local customers manages its listing through Google Business Profile, not through the knowledge panel claim process.
Google's knowledge panel help sends local businesses to Business Profile to claim or create their listing. A larger brand, a franchise or a founder with a public profile may also have a knowledge panel. Our Google Business Profile handbook covers the profile in depth.