The suggestions certainly are mild...
Weight distributing hitches
and
Sway control devices
A "trailering professional" is, of course, normally someone who will make money by selling you some hardware.
There is no requirement or even recommendation to use WD. Larger GM pickups require WD over a specific level, only because their much higher towing capacity means much higher tongue weight.
So why use one? If you know what you are trying to change, you can make a sensible choice.
The basic reason for a weight-distributing hitch is to change the weight (actually load) carried by each axle, normally to relieve an over-loaded rear axle... so if the rear axle is not too heavily loaded, reducing rear axle load is not a reason to use WD. That means the first step is to check that load: measure the axle loads at a scale with the truck loaded for travel, or with it empty and add the stuff you will carry. Pickup trucks are intended to have more load on the rear axle than the front when fully loaded.
The other axle load of interest is the truck's front axle. Some people are concerned that the small reduction in front axle load due to the trailer will cause problems. With a distance from rear axle to hitch ball of about 56", and a wheelbase of 140.5" if you have the longer wheelbase (sorry Jean-Pierre, I don't know which you have) then 40% of the tongue weight will be taken off the front axle; if you have 400 pounds of tongue weight that's 160 pounds off the front axle, or about 6% of the non-towing front axle load. GM's instructions for setting up WD in the Colorado/Canyon's owner's manual is to return the front axle load to what it would be without the trailer, which hints at why they say "A weight distributing hitch may be useful with some trailers".
Sway reduction is the other reason people use WD. GM says
They don't suggest adding any particular type of system, and the WD system can be the sway control system, which avoids adding more poorly-constructed, heavy, and ineffective hardware from the towing equipment industry. Fundamentally, a sway control system is anything that absorbs energy from the relative movement of the truck and trailer, just like making the pivot of pendulum sticky to keep it from continuing to swing.
A ideal WD system by itself actually makes sway worse by reducing rear axle traction, but actual WD systems have lots of springiness in them that tends to push the coupling toward straight, and they have varying amounts of friction (as an unintended side-effect of crude construction, or deliberately) which damps motion of the coupling (such as sway). No truck with ten to twelve feet of wheelbase should have a sway problem with a 19' tandem-axle travel trailer (my minivan handles a single-axle trailer almost that size with zero stability issues), but if you want a WD system for sway control, it would make sense to me to at least use one with lots of friction - the classic Equal-i-zer or cheaper Fastway E2 or similar sliding-bar design, or the Andersen No-Sway which has a conical rotary brake just for this purpose.
If this was a short SUV with a soft rear suspension, WD and sway control would likely make sense. I'm not sure why a truck needs them.