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For video editing, quite a few:

https://www.lifewire.com/best-linux-video-editors-4176979

Openshot and Kdenlive I'm familiar with (I've used the first in an earlier version, and the latter I know by the name, but have never used) - but the others are new to me. I'm sure there are still more than these, too.

Recent versions of Blender can also do video editing and vfx. They're probably also using Blender for that

Not just recent versions -- I just checked my old copy of Blender 2.49b (built on 2009-09-01), and it has the Video Sequence Editor.

Also Blender (most likely). It supports video editing and general vfx, not just 3d asset building. It's also being used professionally for this purpose in a few places too!