Earlier quoted context omitted.
It's been this way for 40 years. Are you a taxpayer? I'd rather not pay for any such retrofit. Furthermore, what makes you think that typos won't be made with any different domain name? Why would a fake hypothetical improvement of the situation drive a massive rewrite of millions of lines of code, server configurations, TLS certificates, specification documents...?
You're vastly exaggerating the costs of changing domains (and setting up a redirect). I'm glad you mention TLS certificate, because those are an ongoing thing, not something you set up once leave unchanged for 40 years.
You can't set up a redirect, because if you leave a redirect in place, then people can send email to the original domain, and we're back where we started with the Mali misdirections. That's what the article is about.