Now imagine there are 2 futures from here on, either joe becomes so much mature and internalizes so much context around the product and your team that your boss realizes it's faster and much cheaper to remove you as the middle man and promote joe to your level and your boss will directly work with joe or either joe starts asking for more money per PR because joe realizes how valuable he is to you and your company
I would be very concerned about what I'm actually paid to do if I can be easily replaced by a statistical text/token generator... Admittedly, not all jobs are new/novel and break new ground, but they've been gunning for Tech Staff for decades. This is merely their latest and possibly most effective attempt. Or it's at least perceived as such.
What if we change the question to be about a human? Say if you onboard a new very promising team member and mentor them into success to the point he/she can take most of your tasks. Are you more or less valuable now?
As far as I can tell, humans are still showing more ability to "move outside one's training set" than various computer tools. When such tools can show reasoning rather than data recovery skills, we'll all have to find new work. But unless they're going to consume goods, the economy needs meat sacks.