This isn't true in my experience, there are plenty of well paid jobs where you don't have to talk to non-technical people. For example, lets say you are developing infrastructure at Google, how often do you think you talk to non-engineers? Never, everyone in your management chain will be engineers, your product managers are ex-engineers, your users are engineers etc. This is true for directors managing lots of people as well as well.
And even when you develop services much of it is just getting the technical parts right so you can work there as well at Google with very little time spent talking to non-technical people, so senior positions there are mostly about technical stuff.
You could argue that Google and other big companies are a special case, however if we exclude low paid jobs where you just earn half of what you'd do at Google or Facebook then pure technical work like this is a very significant fraction of the market. I'm not sure why I'd work on my presentations skills so I could get hired by a company paying me less.
