We who lived through the classic Unix experience also remember how at the time MS/PC/DR-DOS had things that we 300 BPS terminal users could but dream of, like an Alt key that just worked and highlighted menu option accelerators when one pressed it. And function keys that didn't just cause a mess, or beeps, or surprise commands to happen.
Typical users of the 21st century would be appalled when faced with it. And there's probably no retrocomputing enthusiast that is quite that masochistic. (-:
Much of what sysinst does is just farmed out to tar, pkg_add, ifconfig, and other programs. It even handily prints their command lines at the top of the screen when they are running. So someone who wants a CLI rather than a TUI, and not really the actual "classic Unix experience", could just run those programs. And there's probably room for an installer that does the same thing as sysinst but in the old text-adventure-game style of print-menu-prompt-for-line-with-selection for people with printer terminals. (-:
Like AIX 7's installer:
* https://ibm.com/docs/en/aix/7.3.0?topic=system-using-bos-men...
But don't knock full screen TUI programs like sysinst. There's definitely a place for them, and on the commercial Unices, where the vendors had gone to some effort to make the installation and configuration programs user-friendly, they were the "classic Unix experience". SCO had one, for example. They even managed to have it recognize F1 for help.
* https://sco.com/products/openserver6/reviewers_guide2.html
Function keys. F1 for help. This stuff for contemporary Unix people was like the "Classic MS-DOS experience", but at the time when PC users were using GUI installation programs in DOS+Windows 3. (-: