Why standard Indonesian is not spoken throughout Indonesia

Why standard Indonesian is not spoken throughout Indonesia
bbc.com

With that in mind, the statements about Bahasa Indonesian being simpler or more rigid than other languages are more like social or cultural judgments than bonafide linguistic facts.

This article touches on something I've been thinking a lot about lately--the deepness of language. I think people have this vision of a polyglot future with automatic computer translation. I think that's quite short sighted and misses how deep language goes. My mom, who was born in Bangladesh, learned English in school and moved to the U.S. as an adult. Though she has been in the U.S. for thirty years, she will never be able to communicate in English with the level of sophistication she does in Bengali. Indeed, even we (her family who know better) perceive her as someone capable of a limited range of thinking as a result of the limited range of what she can express verbally in English.

All that resulted in quite a shock for us when she started using Facebook. On Facebook, she can sit and mull things over and think about what she wants to say. So we'll be taken aback by her posts quoting Dostoevsky or whatever (she was a voracious reader of classic literature translated into Bengali). It's a stark example how hobbling it can be to be forced to communicate in a language that is not one's own (an idea the article delves into). It also makes me skeptical of any idea that we can establish meaningful communications built on automated translation.

This text is also clearly not meant as a treatise of linguistics about Bahasa Indonesia, it's more of a cultural trivia piece so I don't think it's really fair to criticize the lack of cold hard linguistic facts. It's also an important piece of information for anybody considering learning the language, as it turns out that it might not be as useful as one might guess even if you plan to live in Indonesia.

I do challenge your assertion that "claims about the relative simplicity or complexity of different languages are rarely grounded in actual linguistic evidence". It's true that it's very hard to judge the "absolute" difficulty of a language because everybody has very profound cultural and linguistic biases. It's also true that it's not generally a very useful information, I don't know which of Italian or Vietnamese is objectively harder but I know that as a speaker of French and English I'd probably have an easier time learning the former than the latter.

That being said I think if you're familiar enough with the languages you're "rating" you can come up with a pretty decent classification of "absolute" difficulty. For instance I'd personally consider Portuguese to be objectively harder than Spanish, because while they're extremely similar languages Portuguese does have an objectively more complex phonology and slightly trickier grammar. I would also say that French is "absolutely" more difficult than Italian because of the more complex spelling and phonology.

Chinese is widely considered a difficult language, partly because it's tonal (and you could say that's cultural bias) but also because of its very complex writing system. I don't think anybody could say that the differences in difficulty between written Spanish and written Chinese can only be attributed to cultural judgement.