No - sc and vt are not really xterm-compatible. Likewise teken. The first two are essentially
cons25 (25-line "SCO-like" console), and the last you might call xterm-compromise. The notion behind teken was to lessen distress of people who happen to be on the console and ssh to some other machine where
cons25 is unknown. It amends some of the function keys, and some of the screen-updating.
In ncurses, those have accurate terminal descriptions (with notes):
To get a better sense of the differences of
xterm, you might try running
(to avoid getting distracted by the lack of support for 80/132-column switching). For validating the terminal descriptions,
tack was more useful.
If those terminals had supported alternate screen, there would be a note in the terminal database, and (likely) the
rmcup capabilities would be filled out to demonstrate it.