Dart vs PHP (value in learning)

Nice pro and con comparison.  Note that they reviewed the old Dart 1.24.3 vs Dart 2.0 which is out now and addressed a couple of the cons they site against Dart.  A key takeway from the Slant community is :

When comparing PHP vs Dart, the Slant community recommends Dart for most people. In the question“What is the best programming language to learn first?” Dart is ranked 23rd while PHP is ranked 31st.  The most important reason people chose Dart is:

Dart is a single threaded programming language. So if any piece of code blocks the execution of the program, the program practically freezes. To avoid this Dart makes use of asynchronous operations which let your program run without getting blocked. This is done through Future objects. A Future is an object which represent a means for getting a value at a certain point in the future. A function may invoke a Future and when that happens, two outcomes can be achieved: 1. The function is unable to return a value, so it queues up work to be done and returns an uncompleted Future object. 2. Or later when a value is available to be returned, the Future object completes with that value.

The full item is here:  https://www.slant.co/versus/125/383/~php_vs_dart