I have hundreds of screencasts I recorded where I record my desktop and sometimes a webcam in the corner. These screencasts are put together to create a video course, so they need to be super polished.
With Camtasia it takes seconds to add really really nice looking tooltip pop ups, various text styles and arrows, smooth zoom / pans and even really neat animations that can be applied to anything.
For example check out the intro video on https://diveintodocker.com/. That entire animation (and video) was made in Camtasia in a few minutes without needing to do anything other than drag a few sliders around until the speed was right and it looked reasonable. Camtasia is an all purpose screencast editing tool but they have no Linux port.
I tried everything. Kdenlive, Lightworks, Shotcut, Open Shot, DaVinci Resolve and even Blender. They are all much much worse than Camtasia for editing screencast style videos (which are mostly around adding context related popups, dimming areas of the screen, adding text overlays, zooms, etc.). Worse as in, after 8 hours of trying to reproduce that Docker intro in Kdenlive I still didn't have anything that looked good with nothing in sight that would hint that I could do the things I could do in Camtasia. That was as of 2 months ago too.