I think this is true for the vast majority of us technically inclined. There are definitely outliers that can code their way to success, Linus, Carmack and many more. But they represent the very few.
We have to contend that most systems that are worth acquiring revenue are systems that require groups of people. Once we're at groups of people, social interactions really matter whether we like it or not.
I've known engineers who are perfectly great in their technical skill, but ideologies of perfection to syntax, build systems vs the rest of the team started becoming friction points. Soon it led to full on mediation sessions with threats of formal complaint.
Understanding that some things are not worth souring relationships over or how to deliver feedback in a firm by helpful way without creating needless friction are very important tools.
Recently I've been missing a bore basic skill: how to writ ebusiness emails. I spend about 50% of my email-writing time making sure I don't sound like I'm talking down to someone, or treating a co-worker like I'm their boss.
The real skill is being able to NOT read into the email anything but what is there....eg: not making assumptions that the writer is talking down to you.
IMO that is a harder skill to learn than writing the email!
I'm kind of annoyed by the amount of articles explaining this, but nobody cares that a vast amount of developers have no technical skills whatsoever, but since they're hired by other non-technical people, nobody notices, and they somehow "perform well" in those environments.
Well this 2005 post from Joel Spolsky claiming that most people interviewed for a programming position can't code got a lot of attention. https://www.joelonsoftware.com/2005/01/27/news-58/ So it's not that 99.5% of all people can't code, but "the worst 199 keep applying for every job and never getting them". If you don't have screener questions, chances are higher that you have developers who can't code.
We have to contend that most systems that are worth acquiring revenue are systems that require groups of people. Once we're at groups of people, social interactions really matter whether we like it or not.
I've known engineers who are perfectly great in their technical skill, but ideologies of perfection to syntax, build systems vs the rest of the team started becoming friction points. Soon it led to full on mediation sessions with threats of formal complaint.
Understanding that some things are not worth souring relationships over or how to deliver feedback in a firm by helpful way without creating needless friction are very important tools.
So I agree, soft skills are worth developing.