gnome-tweak-tool

> I've been hearing that text-mode support and/or 2D support will vanish entirely from video hardware for ages,

Any part of the '2D acceleration hardware' has been gone for a while now. At least from modern hardware. Any sort of acceleration support based on 2D hardware is done through emulation, if it exists at all.

VGA mode and such things are more related to modesetting which is a bit orthogonal to that issue.

Modesetting issues were one of the biggest, if not the biggest, reasons to keep the old driver framework inherited from XFree86. Without modesetting support you couldn't really display anything useful on the display, especially if your display isn't one of the 'standard' resolutions and support for that resolution wasn't programmed into the BIOS (a typical issue on old pre-GMA Intel IGP laptops)

Now that mode setting has moved to the kernel rather then in the XServer having the Xserver direct access to hardware or their own special drivers is more of a detriment then anything else. Hopefully Wayland turns into a usable solution for running X applications on Linux since it will simplify the driver situation quite a bit.