Avid was picked up by a lot of people used to using their system before the digital switch. Premiere Pro became big, partly because of its seamless integration with other Adobe products (Photoshop and After Effects were being used widely in the industry already). Final Cut had its Hollywood heyday in the early 2010s but has fallen off a bit since then. This is for a collection of reasons, but the biggest is probably because it isn’t compatible with Windows, making it difficult to have a collaborative workflow.