Some of it rings true, some of it does not
As someone who has quite successfully worked exclusively from home for the last 8 years, here are my 2p:
1. You need a proper office, for work, the family table or any shared room is not an office. If you do not have one, build one (a proper log cabin is ~ 3k so it is not that expensive).
2. You should treat going to your home office same as going to any office. While work casual is fine, PJ definitely are not.
3. You need separate proper comms - there are plenty of VOIP providers, getting any number of numbers for home office use is trivial. Cameras for the video conf rig are also not something to save on. Get a proper high end logitech, even if you always crank it down after that. Separate broadband is stupid and usually is not worth the hassle. Get a QoS capable router and split the network with bandwidth allocations (you need that for VOIP anyway). Anything running OpenWRT can do that with ease. Splitting is a must too - your work stuff does not belong on the same network segment with junior. Similarly, once you are done for the day you should be able to move to a part of the network where you cannot access work without going through a few hoops.
One thing I do not quite agree with the article. It fails to reflect the realities of working for a company outside the UK which is one of the most common work-from-home scenarios. For those you end up taking 2-3 hour team calls while at the dinner table on Friday or more often while at the kitchen table with knife in hand and a pot on the stove. End of the day you are spending 95% of the time listening on those, so you might as well make use of the fact that it is encroaching on your beer hours due to the TZ difference. If something requires you switching your attention to the full you can always go into your home office.