I went to a unicode meeting about a decade ago, and asked one of the luminaries over beer one night. He told me that they did some practical research, including reading newspapers and talking to editors. In Japan they would ask questions like "I see that you mention Shanghai in today's paper, and you use Japanese glyphs for the city's name, not the same as Chinese newspaper use. Why?". The answer was generally "that's how we write Shanghai here" and out of that came Han unification.

I suspect that if you could find a couple of mainstream publishers in Taiwan or Japan that prefer to print the names of mainland Chinese using the same glyphs as are used on mainland China instead of the glypths used on Taiwan or in Japan, you might be able to reopen the discussion of han unification.