If you reread the article, I actually say you should add a meta header regardless of whether you do or don't want to send headers.
Why? It actually solves your "next in the TODO list". Most web sites that shouldn't send referrers don't use <meta name="referrer" content="never"> so will be leaking referrers to other web sites. Adding this meta tag will eliminate referrers in both HTTP and HTTPS.
So yes, my own preference is to keep HTTP Referrers, but I also explain how to kill HTTP referrers for webmasters who would like to as well.
I disagree with your suggestion to use such a meta tag, because it's an opt-out scheme. People should not have to opt out of potential privacy leaks. If a web page does not specify any referer policy, I think the default should be no referer.
Unfortunately I still can't remember the website where I found the "bullshit" argument, and it's not in my history because I probably ended up using a different browser to comply with their no-access-unless-you-accept-3rd-party-cookies policy. But if you understand why people like me want third-party cookies to be disabled by default, I think you'll also understand why I want referers to be disabled by default, too. It's not about user control as @untog suggests, because the user is always ultimately in control when it comes to HTTP headers. Rather, it's about having secure defaults.
I didn't realise I missed a point to address, I'll seek to clarify.
It's always the user's choice as to whether to send referrers or not, as the referrer is actually added by the user's web browser itself. Extensions exist for just about every major web browser[1][2][...] to modify the behaviour of the HTTP Referrer field. If you don't like the idea of sending referrers, it's entirely within your control to never send a single referrer.
In almost all cases, disabling the referrer entirely won't result in any broken behaviour, primarily as the HTTP Referrer is unreliable and can be spoofed anyway.
Why? It actually solves your "next in the TODO list". Most web sites that shouldn't send referrers don't use <meta name="referrer" content="never"> so will be leaking referrers to other web sites. Adding this meta tag will eliminate referrers in both HTTP and HTTPS.
So yes, my own preference is to keep HTTP Referrers, but I also explain how to kill HTTP referrers for webmasters who would like to as well.