Suzanne S. Barnhill shared this with us in
microsoft.public.word.newusers:

Your reply assumes that WordPerfect will still be around in ten years.
Perhaps it will. I have no doubt that Word will be. FWIW, I have had
no problem opening Word 2.0 files in Word 2003.

Your conclusion is flawed.
I observe that Wordperfect existed 10 years ago, and still exists today.
Concerning Word, that is your opinion. Here in Europe there is much
pressure from governments towards Open Standards. So either Microsoft
starts using Open Standards, or it's out of business in Europe.
Remember Munich (Germany), Bergen (Norway),...