The one I worked on had a tape drive, paper tape read / punch for CNC machines, and an analog joystick.
It had a very powerful Basic that included a ton of graphics primitives, capable of many of the images shown. There was a demo tape similar to that video.
Storage tube CRT.
Editing text was done a screen at a time, overwrites done right over existing characters.
When it all got a bit messy, just refresh and carry on after it rendered current text to the screen. Sometimes, and this was often true for the files we were creating, multiple columns could be used to get a lot on the screen to work with, depending on widths.
The higher end ones did something like 4k pixels x 3k pixels.
If you wanted hard copy, you sent it to a pen plotter, or took a photo of the screen.
For text I/O, tape or paper tape.
I was 19 at the time. Had a chance to get one and didn't do it. Still regret it.
Now that we have these nice 4k displays, I am tempted to go find or write an emulation.
I think the CPU was a 6800 running at maybe a few Mhz, or maybe just 1Mhz.
The old "xterm" program has "Tektronix mode" as a command line option. One could send the graphics data and get a scaled bitmap output. I used to do it on SGI computers.
Seems like a similar dynamic to what these displays offered.
I got to work on one in the mid 80's
No scrolling, and multi-column output made sense.