I don’t think DVDs look bad on a 1080p TV, others that assume they will may be surprised!
Or hooked their DVD player to the HDTV with an RCA cable and were disappointed.
On the flipside, if you had a DVD player capable of progressive scan and Component or HDMI-out, it's fine for couch viewing.
That said, there are plenty of DVDs out there (extreme case, single layer DVD with extras on same disc as movie) where the bitrate can show, but that's not a fault of the format.
If your TV is under 50", I don't think you'd notice quite so much.