Professionalism and the tech industry are just starting to get acquainted.
For instance: ask a lawyer what they think about the overturning of Roe v Wade. Now ask them what they think about their colleagues who disagree. Don't forget to duck.
Which isn't to say that we wouldn't all be much better off with more distance between our opinions and our identities. But the thing you're looking for is a cultivated practice that is often not at odds with 'egotism' (what is that, precisely, anyway?) but _entailed by_ it: the not-wanting-to-be-the-kind-of-person-who-does-XYZ.
Not all vanities are risible.
What you're looking for is a long-cultivated, inward practice that can be supported or hindered by all the usual forces, local context (culture, practice, etc) chief among them.
Put another way: your claim isn't that most programmers are unprofessional. It's that they're _uncollegial_. And you're right. So are a lot of other contemporary professionals. It's a shouty era.
I've found that it's extraordinarily valuable to separate these two cognitive modes wherever possible.
As I read this while sipping my turmeric latte my monocle popped right out!
99% of [people], but especially the brilliant/well known ones [in any domain], are insufferable egotists.
IMHO this is normal. When somebody puts in a lot of effort in mastering something they intrinsically know that they are better than most people in that something. As social animals, getting "noticed" is a form of being conferred "status" in the group. Thus you tend to "act out" to acknowledge/confirm that recognition. It is fine as long as it is within acceptable social bounds and not out of touch with reality.