That's why I explicitly wrote electronic typewriter.

Electronic office typewriters did have interfaces for monitors and some came with integrated digital storage (e.g. disks) and had a similar feature set to that of early word processing programs.

I think a distinction needs to be made between electric typewriters (basically electrified mechanical typewriters to not tire out the fingers) and electronic typewriters (more advanced devices, usually with a buffer to correct typos before they are committed to paper, might have spell check or other intelligence, sometimes feature a full-blown built-in display). The latter are basically computers, but they are self-contained with regards to the peripherals and printing.

On the other hand, a DOS operating environment, while slightly more complex, is far easier to integrate into a modern workflow. The environment can be emulated (= easier to lug around a 4MB DOS disk image than a 20kg chunky suitcase, easy to use modern peripherals like 4K screens, KVM switches/Alt+Tab, and WiFi printers), data backup is very straightforward (vs a machine-specific process or paper photocopy), and the data is far easier to convert to modern formats for incorporation into modern workflows (US ASCII + Markdown can be turned to PDF, HTML, ODT, or kept as is).

If I had to incur the complexity cost of a more advanced platform, a DOS editor would be preferable over an electronic typewriter.