They all did the same thing, but in different ways.
PID Wiki kinda shows it's just a mathematical calculation and can be implemented in a bazillion ways.
I could not agree with you more. I have cooked on a Cookshack, Yoder, and now Blaz'n and I have always felt the PID discussion is overblown. All of the controllers/units I have used have produced some great Que. I see the PID discussion more as markerting than anything else. Other views may vary 
I beg to disagree. Yes you can make good Q with either, but PID is an improvement in cooking management IMHO. I suspect that eventually, all the major pellet pit makers will incorporate them into their designs. Main concern is the price difference between digital type and PID type, which I expect will be resolved with demand.
Bet we all remember the cost of the early LED flat TV. Outrageous then but now about 1/4 of the cost. As for advantages of PID over the standard digital, first is the ability to adjust it to your pit. The algorithms can be adjusted to make sure the selected temp is very close to the actual temp on the grill grate. For the more sophisticated (you know who you are) there are several other adjustments that are available. There are complaints that tighter temp control results in less smoke flavor in your finished product. That is adjustable also, and most PID controls are set to produce more smoke at lower temps. Bottom line--Progress, don't knock it. Go with it. 
Although my favorite controller is the Savannah Stoker controller, I very much disagree with the bolded part. A straight up PID controller falls 3rd on my list.
My personal hierarchy of controllers:
1) Savannah Stoker (Hybrid - because it can run in PID mode or completely disregard the PID algorithms) -
What puts this controller on top, in my opinion, is its ability the ignore the PID when I want it to. This controller lets the end user run in PID mode or manual mode (completely ignoring the PID) and runs at a constant duty cycle (perfect for grilling). It lets you set the low duty cycle and high duty cycle in 1% increments, meaning I can use it on my Traeger and have my Traeger run anywhere between P5 and P0 as it needs to maintain around 150* for smoking jerky. Set up properly for the cook, even if I open the door to do something the controller will never dump more than my high duty cycle which can be set similar to P0, P1, P2, etc., whatever I choose for that cook.
2) Fast Eddy PG500 type controller - This one is not PID. It lets the end user pick the low duty cycle and the high duty cycle. It just oscillates back and forth depending on whether the grill temp is above or below the set temperature. You can have the duty cycles set the same or 1 setting off from one another and have a constant flame for grilling. That is something a PID controller does not do. You can adjust the low duty and high duty cycles so you can control the temp swing to some degree. With a PID, you are at the mercy of the algorithms and the temp swing is what it is.
3) Straight up PID controller or any other mathematical driven controller - This is your Yoder, Rec Tec, GMG, etc. They do a fine job at what they are designed to do, maintaining smoking temperatures in the pit. They are not designed to maintain a certain flame for grilling or give the end user options to limit the low and high duty cycles for certain situations. There is no adjustment for temp swings. They do what their math tells them to do.
4) Simple controllers that have set low duty cycles and high duty cycles, that for the most part, are not very adjustable. This is your Traeger digital controller and Ortech controller.
5) Lastly is the Traeger low/med/hi controller.
