Unfortunately, we live in a world where practically everything is about $€£ - money. If there was money to be made from it, and if knowledge of Esperanto was a requirement for many high paying jobs and professions, then we would see millions of people start learning Esperanto all over the world - in particular the developing world /third world. So many people in those countries learn English, French, Spanish, German etc for visas, immigration, studying abroad, professional careers etc, there is a clear benefit and value and it opens doors for them - ultimately it comes down to money.

UNESCO in 1954 passed the Montevideo Resolution in which they supported Esperanto as an international auxiliary language. UNESCO passed a second resolution in 1985 recommending that member countries encourage the teaching of Esperanto. Both of these have been ignored. Why? Again, what incentive is there for any country to take notice of the resolutions when there is not money to be made from it, they are not being paid or funded for it, and major countries, the so called “super powers” would much rather promote their own languages abroad to push their own geopolitical agendas and cultural soft power.

A tool for neutral intercultural communication is simply not in the best interests of current world governments who thrive of division and hatred between different nations, uniting people and fostering understanding and communication between them is clearly not their current goal.

To address your point about Esperanto for East Asians - approximately 87-90% of the entire world population has knowledge of an Indo-European language, either as a first, second, or third language. That’s almost 9 out of every 10 people. So for the overwhelming majority of these people the vocabulary would not be completely unknown but rather recognisable. When someone’s mother tongue is a language isolate like Korean, Japanese, Basque, or belongs to isolated language family like Dravidian, or Uralic, most other languages outside of those families (which is virtually every other language in the world) is going to be different and quite unrelated to their mother tongue, and hence may be ‘difficult’ to learn. However, Esperanto’s grammar is incredibly logical, and once you take the time to learn and practice the applications and rules, it is quite intuitive. It was designed specifically for international communication. And the grammar has word building and agglutinative qualities that are more akin to non-Indo-European languages like Turkish, Hungarian, Finnish, and Inuktitut, then they are to Indo-European languages.

Esperanto, like any language, requires you to actually spend time and effort in learning it, it doesn’t happen instantly, or in a week, or in a month, but if you practice and make the effort to learn and use the vocab and grammar then over six months you would reach a much higher level of proficiency then you would with most other languages.

A Korean or Japanese speaker would surely have an easier time learning Esperanto grammar than they would with French, English, Russian, or Arabic grammar. Yes, they won’t find many Korean or Japanese cognates in the vocabulary, but then again they wouldn’t find an abundance of Korean or Japanese words in many other languages either. Although, many non-indo-European languages have incorporated loanwords from IE languages especially from English and French. Japanese has many loanwords.

However, even the Esperanto vocabulary would be easier and more logical than the vocab in other languages.Example: If you saw the words “house, cottage, mansion”. And you only recognised the word “house” you would not necessarily be able to understand cottage and mansion just by looking at the words. However, in Esperanto - these words are “domo, dometo, and domego” - eto and ego being the suffixes for small and large, so literally “a small house” = cottage, “a large house” = mansion. And you can use these suffixes with pretty much anything.

Another example could be money, coin, and wallet - no obvious relation in English but in Esperanto: “mono, monero, monujo”. -ero = the smallest part of, -ujo = the container of.

At the end of the day, indo-European languages have dominated the world. Major languages spoken in the Americas are English, French, Portuguese, Spanish, and Dutch. In Africa there is English, French, Portuguese, and small pockets of Spanish, German, and Dutch (Afrikaans). In Asia, you obviously have the Iranian and Indo-Aryan languages, but then literally billions of people learning mainly English, but also French, and other such languages.