I think all modern TVs sold in former or present WST regions, still have teletext decoders built in. My brand new Samsung telly has a TTX/MIX button on it. I bet if I tuned to an analogue carrier and set a preset, pressing it would result in a P100 top left corner of the screen
It's probably mandated for accessibility reasons, isn't it? I'm not sure whether there any devices for the deaf that would still utilise it, although you can still use it to read old teletext pages off VHS recordings, if you (and your VHS player) were so inclined.
Interesting, or possibly not, that six years on from the completion of digital switchover, subtitling hasn't changed at all. It's the same four colours (white, yellow, cyan, green) in black rectangles (they used to mix it up a bit with coloured backgrounds for non-human characters in sci-fi, but they don't even do that any more!).
I remember seeing a bit on
See Hear!
many years ago about an effort to update subtitling, with animations for emphasis, font variations (bold and italics) and so on, but nothing ever came of it. They were also talking about switchable sign-language-interpreter overlay streams, which also hasn't happened.