Detective

That's simply not true. If you set the right profile in your control panel (ex. Ryzen balanced), the cpu will lower the frequencies as needed.
In fact Ryzen processors are BETTER than Intel processor, as they have better "granularity" or whatever is called, basically they can switch more often within each second compared to Intel processors. Kind of like if Intel processors need 25 ms to jump from 1 Ghz to 4 ghz, the newest Ryzen may need 4 ms or 10ms to do that.
 
Also if you look at the picture you actually quote , you can see that the processors already does that. His cores consume an average of 1.3w (10.28w / 8 cores = 1.3w) at the moment the picture was taken.  A core doesn't consume so little power at the peak frequency, so obviously his cpu idles at lower frequencies.
 
@Detective you have two fans that are running at 2800 something rpm .. .chances are those fans run at 100% pointlessly making too much noise.  I'd suggest maybe moving them to headers that allow you to control rpm speed (if any available)
Maybe revisit how you placed the fans, how the air moves ... on most cases it makes most sense to have 1-2 fans in front of the case sucking air into the case and blowing it towards the video card and cpu. Then, have fans pulling air out the case on the back of case and top of case. Warm air will rise and get out.
 
Also a completely optional thing... The cpu is probably configured on auto voltage... i see there voltages for cores at 1.41v, 1.44v
The default voltages are acceptable but may be pointlessly set too high, making the cores consume a bit more power than needed.
If the bios has an option to set a voltage offset, maybe see how your cpu behaves with a 25-50mV offset ( - 0.05v offset) .. basically instead of 1.41v, it would run at 1.36v
Depending on the quality of the silicon, the cpu could run perfectly fine as if nothing changed but you get cooler cpu (or same temperature but fans spinning at lower rpm because they don't need to run as fast to keep the cpu at that temperature level).
If you're a bit less lucky, the cpu won't be able to reach that peak 4.2 ghz or whatever and peak to 4.1 ghz or 4.0 ghz and you'll get maybe less than 1% performance loss.

This is normal for Ryzen. Ryzen doesn't downclock during low usage like intel does, so it's always running at high speeds regardless of load, which produces more heat. Also because of the 7nm process used by Ryzen 3000 chips, the dye is physically very small so the heat is concentrated in a smaller point under the IHS, making these chips extra hard to cool, including under load.

Perhaps try increasing the CPU fan speed? it's quite slow imo, unless you're trying to have a quite build.

As long as the temperatures stay under 85 degrees, you CPU will be happy. Between 85 and around 90 degrees it will start to reduce the frequency of its cores in order to consume less power and therefore produce less heat and cool down gradually if the cooler/fan does its job.  if the temperature stays high it will eventually shut down.
 
Your motherboard seems to adjust fan speed dynamically keeping your cpu around that temperature. It does it to keep fan speed low, making your computer less noisy.
You can go in bios and see if there's a fan curve configurator, where you can adjust the minimum and maximum fan speeds versus temperature, to have your fan spin at faster speeds even when it's cold enough.

yea, idle temps dont really matter as long as load temps are good.
also use hwinfo64 or ryzen master to monitor ryzen temps correctly, and hwmonitor is broken and is not really accurate.

your temps are more than fine, as i said idle temps dont matter as long as load temps are fine.

I'm honestly on the nvidia side too, had had 3 nvidia GPUS so far, so I may just stick to them. Also, for sure will do that overclocking research, I've always thought that OC'ing is something extremely interesting and pontentially fun to do, and I've always wanted to learn the basics and a bit more of it, instead of just researching the CPUs common OC configs, I'd prefer finding them myself.

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I couldn't bring myself to spend close to $25 on an cable management solution so I came up with my own and I think it's honestly a lot better!
 
All that's needed is:
a roll of Velcro Hook and Loop a heavy stapler like the T-50 I have:  

 
 
 
1. Cut a piece of the velcro enough to wrap all your wires, plus a bit extra and staple it under the desk
 

 
 
2. Wrap up your wires! That's it!
 

 
 
The benefits of this is that it looks a lot cleaner (in my opinion), it's modular to fit your needs and is a TON cheaper than any other product you can buy. 
 
Here's an image of what it looks like: 
 

 
Let me know what you think!