They get away with it by being a well established known player with a long history of trustworthiness and branding. Github enterprise is not a guy I've never he

They get away with it by being a well established known player with a long history of trustworthiness and branding. Github enterprise is not a guy I've never heard of just saying "Hey run this closed source binary on your computer." They also offer an amazing product that was revolutionary when it first came out. They weren't copying an already well known good product. There are some open source competitors now, but they had an enormous head start.