1) point out how heavy they are. Give them a facsimile to lift to show them, after making them sign a waiver that they may permanently injure their back doing so.
2) show them how deep they are, and how far away from the wall they must sit because of this.
3) show them two power meters, showing the power consumption of a CRT and a modern LCD for comparison. Also show the actual costs for that power, and how much typical usage of these displays will cost per day and per year.
The last one alone should dissuade most people from wanting to go backwards.
Most people don't give two shits about latency, and modern LCDs with >= 120 fps capability already exist.