Interesting article. Having used suspension posts on all my bikes due to back pain, I can say that the #2 and #4 reasons not to use suspension posts in that article are wrong. Or more accurately they are the sort of reasons someone comes up with who needs an article that has a list of reasons, and comes up with a list that sound valid, but are not based on experience.
Suspension bob should only occur when you have picked the wrong elastomer if using an elastomer post like a Thudbuster, or have dialed in the preload wrong on a spring-loaded post like a Animaris or a Kinekt. On the Kinekt that could also happen if you have the wrong spring on.
As for the 'no fat bikes because they diminish effectiveness' this is just flat out completely wrong. It sounds common-sense-intuitive but it lacks an understanding of how suspension works. I started using suspension posts on fat bike commuters and they totally eliminated lower back pain from hitting potholes at speed. Thats on pavement with high pressure. What suspension posts do is provide
additional suspension effect. The 'diminished effectiveness' argument assumes there is a single fixed level of total effectiveness and thats all you get, so its split between two elements rather than fully used by one. That is not the case.
Anyone who owns a fat bike for long will tell you fat tires at any pressure, overland or on pavement, provide some suspension effect, but it is not at all a substitute in any way for rear suspension. its more like a minor side effect. A suspension post on a hardtail fat bike is the closest thing you will get to a full-suspension fat bike, which is desirable since there are so few
quality FS fat bike frames (Salsa Bucksaw was probably the last good one).
Suspension stems are another issue - and my personal opinion you chase that dragon ONLY after you have settled on the right handlebars and right riding position,
I use Kinekt suspension stems and the only reason I do is because of a wrist injury that is effectively never going away. The conclusion here not to pursue this until you are sure you must is on point. You are much better off with a suspension front fork. But only if you can't have one of those, the Kinekts are the best-in-class just like their seatposts (and by far the most expensive). The kicker with suspension stems is your upper body leaning over (if your cycling posture does this on your ride) can at rest fully compress the suspension stem so its fully extended with you just sitting on the damn bike, never mind going over terrain and having it absorb shock. Kinekt has a bumper/damper upgrade that helps with this, coupled to an XL spring you can buy that is off-list (its a max-load seat spring that is the same size as what they use for the suspension saddle). They may be advertising this spring upgrade now but when I talked with them about the problem it was a new idea they came up with. Regardless of your body weight you need to go this route if doing a suspension stem. Get one that doesn't bottom out and they are awesome for reducing wrist pain and fatigue.
All of the above assumes that your ergonomics works with the available stem lengths. This goes hand in hand with choosing handlebars with the right rise and pullback, as well as maybe tinkering with the setback on your seatpost, or saddle position on the rails. Fitment as noted by
@fabbrisd is crucial and thats not as much of a slam-dunk as it is on a bike like a Specialized that may use proprietary components (like their proprietary stem that may be in use on your bike?).