Technology

Probably, as I imagine that if it can display a configurable prompt, it can send whatever escape sequences it wants. Like, I expect that one could set it to show the prompt with whatever colors one wants. But it won't govern what software does to the terminal subsequent to handing off control to that software.

My system uses agetty. From its man page:

  The issue files may contain certain escape codes to display the system name, date, time et cetera. All escape codes
  consist of a backslash (\) immediately followed by one of the characters listed below.

  e or e{name}
      Translate the human-readable name to an escape sequence and insert it (for example: \e{red}Alert text.\e{reset}).
      If the name argument is not specified, then insert \033. The currently supported names are: black, blink, blue,
      bold, brown, cyan, darkgray, gray, green, halfbright, lightblue, lightcyan, lightgray, lightgreen, lightmagenta,
      lightred, magenta, red, reset, reverse, yellow and white. All unknown names are silently ignored.

So if you insert the relevant escape sequences into /etc/issue, you can have the login prompt screen be whatever set of colors you want.

I don't have agetty do that, but I do use emptty on tty7. emptty is a console-based display manager -- that is, I log in on a console and then start Sway from that. On Debian, emptty defaults to showing a color prompt (I mean, it's a light-on-dark prompt by default, but I'm sure that one could set it up to do whatever).

EDIT: /etc/emptty/motd