It is fair to acknowledge that with new levels of technology something that we valued gets lost. Consider writing, before writing became widespread, people's memories had to be much more elaborate (remembering who owed who for example), oral storytelling culture was stronger and perhaps people with the best memories and oratory skills were the most valued in society. With writing that got lost. There are countless examples big and small where new bit of tech completely demolished something that was genuinely deeply valued. But you know what, people move on and find other valuable things to do and value. The reason why the 25 Field Medalists who signed the letter could do their work at all is because writing and books existed, probably because computers freed up their brains, and civilisational wealth paid their salaries. If solving maths problems gets automated, we'll definitely lose something. It shouldn't be trivialised and it will hurt. But I don't want to live in the world where we choose to block off the future in the service of protecting the feelings of those who lose out. If Maths is actually important (absurt to think that it isn't), then automating it surely must lead to unimaginable technological developments. How can we compare this future with the current state of solving 1/7 millennium problems every 30 years (at best). It sucks, we should acknowledge that, and go full speed ahead.