Right after the tightly thought out keybindings, I think the greatest value offering in vim is the documentation. It's extremely comprehensive, and being fairly conversant in Vimscript I know I could develop plugins without internet at all, looking up the API with :help (I've only recently acquired the habit and it feels great.) So if vim came out with such a mature, thorough documentation, it would not only be well worth the 100 euro, but I think it would have little problem finding at least a cult following out of thin air. Writing those docs are arguably as hard as writing vim itself, perhaps harder because it isn't as challenging and requires pure dilligence and thoroughness. It's like writing a full book to ship along with the software.

Selling.. though point. I was never good at making up prices.

Buying it for a 100 euros? Yes, in a heartbeat. It's the single most important tool I use.

id suspect VIM would have a very hard time if it was coming out now and nobody knew about it, even for free. That doesnt mean its not awesome, but VIM is all about its legacy, huge ecosystem and hype.

The question is not how much you can sell it for, the question is about how valuable it would or could be.

So while it's unlikely Vim would ever sell, then or now, for 100 euros, VIM is worth that much both then and now. Discovering the VIM text editing features today for the first time is just as impressive as discovering them 20 years ago.