The only frustration I immediately notice is strong reliance on white space for syntax.
* This makes life harder in a modern world of various operating systems and high distribution. Some means of distribution mutilate white space. XML language design spent enormous effort considering for this.
* Line termination differs by OS. Now it’s largely just posix vs Windows, but there used to be even more variance and there could be more in the future.
* Parsing around white space is severely misunderstood by people who do not write parsers regularly. Just this weekend I encountered unique white space syntax added into React’s JSX to compensate for this that doesn’t exist anywhere else in either JS or XML.
* As somebody who maintains a popular code beautifier I have had to learn the hard way that people really enjoy flexibility around white space. They deliberately use my software instead of, or in addition to, the popular software coming out of Facebook because of the flexibility my software allows. The bottom line for many developers is that code beautification can be fully automated and is better performeded by computers and should never be a factor when authoring code.
* code beautification is also highly subjective. Everybody has different opinions on beauty and easy to read. Providing the means to allow developers to exercise those opinions dynamically and automatically makes people happy. So long as it’s just vanity the code stills executed and reads the same way.