I would put that in a grey area Joe.
You end up with mixed results, and there is no 'right' answer when it comes to buying your first microcontroller. There are however 'right' answers when there is a given project that needs to be accomplished, but the differences only make a difference in some minute details.
I've learned on a BASIC Stamp and a PICKit and would encourage others to learn micro-controllers on a more basic level before using some of the more advanced items.
Of course, there is always a RaspberryPi or other SoC... you can program in Java, PHP, Bash, etc and control the pins, but this is not really learning microcontrollers. It's more of an intro to encourage learning the electronics you would use as add-ons.
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I’m not so sure that it is grey at all. I have been involved in both worlds for a long time. PIC requires a programmer, but it is possible to make one yourself. PIC has learning type development boards, but the most popular of them is the one with the most support, and I would have to give that to the LabX board from Microchip. That board can cost from $50 for a used, older rev, up to much more for a new recent model. Sure there are a lot of others, but the LABX is the one that has many books written about it in an effort to teach programming. Others cost way more, and have limited support by the company who produced it. There are free compilers for the PIC, but if you want a Compiler with similar support as Arduino, you may have to stick with the student version of PIC Basic. The program is limited to small code size, but there is enough space to learn about Pic Basic programing.
It is true that a lot of this is subject to opinion, and that is all I have here, is my educated opinion.
Arduino was designed from the ground up to support free open source micro controller education. It is the most used micro controller of its type in the world. It has the largest collection of free support in the form of people, web sites, and documents for free down load. The UNO can be bought from any number of manufactures, and they are all the same. I have bought many for $6.95 and free shipping. In many cases, the board will come with the USB cable to connect it to a PC.
The compiler is also free, and so are at least hundreds of library files. The libraries cover the use of sensors, and displays, of every type. The libraries have an equal level of free support. The word Free does not come up when you talk about a PIC.
True, it is very easy to learn Basic, but I happen to know basic, and I found C to be almost as easy. With Arduino there is only C, and that is for good reason. C programming is widely used throughout the business, and academic world. The same cannot be said about Basic. The only true statement about basic is that it is easy. Knowing C can lead to a job that pays very well.
The way Arduino teaches is awesome, and it speeds up the learning process, as well as keeping it fun for the student.
Between the PIC and the Arduino I would say that they are opposites when it comes to learning. The Arduino is easy, and fund to get started, and it is fun to progress through learning, with the process going into more complication as you get further into the programming of microcontrollers. The opposite can be said about PIC, it can be a bit complicated to get started, and the complication will continue for a while, getting easier as you go. This does not address the programming language, because you can program the PIC in C too. The problem with the PIC process is that everybody learns at a different speed, and in fact, in different ways. Many people will quit studying the PIC long before they get anywhere, and getting anywhere is the whole goal with Arduino. You will get somewhere on the first day. On the first day almost anyone will have a program running that controls something on an Arduino. How many days, and how much money do you think it will take the average person to get anywhere with a PIC?
Currently, this is my opinion on the best way to get started in learning about using and programming microcontrollers. I don’t see that changing anytime soon.