Kajabi's pitch is "stop stitching together five tools." Course delivery, email marketing, landing pages, community, payments — all under one roof. The price reflects that. For creators doing $50K+/mo who don't want to think about plumbing, it's a fine deal.
Thinkific is the course-focused alternative — cheaper, more flexible on integrations, better answer if you already have email + landing-page tools you like. The course player itself is on par with Kajabi.