This is an important point. My light-bulb moment was when I talked to a product owner in a previous job, and I expressed surprise around an expensive planned change, because it didn't seem that valuable to our customers.
He said, "Almost half of what we do is not that valuable to our customers, but it's valuable to him, and her, and him", pointing through the conference-room window at my fellow programmers, "and that's why we do it. If we only did things that were very valuable to our customers, we wouldn't have nearly as many good engineers on the team as we do."
A better way to put it is that these things do have value to the customer, the customer just doesn't have a way to understand how the work you're doing provides value because it's the part of the product you don't see. If you clean up technical debt, improve test coverage, improve your deployment systems, etc, it doesn't change the immediate customer experience in a meaningful way, but it does allow you to deliver the changes that customers do see faster and with fewer risks.
This quote makes it seem like the work is self-indulgent, and I have seen that happen sometimes, but it's not half of what we do.
Certainly puts "good" into perspective
Perhaps those “good engineers” need a reminder of who enables their situation to exist at all.
Are you all hiring?
I mean if half of what you do isn’t delivering customer value maybe you don’t need to have as many good engineers on the team as you do.
Do the engineers not derive enjoyment in their jobs from making the customer experience better? This does track with what I've experience in my career, where we've gone from everything being to better the user experience to tech companies sort of trying to out-do each other in their technical solutions while the software continuously gets worse and more antagonistic.