hindsight is 20/20. It would be quite easy for a team of developers and product managers to get together to discuss "how we take what we have and extend it to cover the new use case" rather than "what is the best approach for the new use case".
The problem I have always had with the analogy of a person holding up the books with their back is that a table doesn't have to do "work" to hold up the books, but a person does. They table isn't burning any calories.
the subject of race has to somehow be implied or involved for the comment/person to be racist. No one is claiming racists will just tell you its a race issue.
I agree with you that the world is nowhere near "doomed" or even heading in that direction. It's not fair to claim racism here, however. The poster did not mention anything about race.