A language is not just a system of communication, it is a unique view of the world and one or more cultures within that world. Anatole France said that "to learn a language is to gain a soul."
If the US had adopted German or French I am pretty sure we would have landed on the moon as well. English is no better or worse than either of those languages for communicating scientific and engineering skills. English is very difficult for poetry, but it is easier to make oneself understood in simplified English than in any variety of Russian, for example. It is nearly impossible to spell everything correctly, because the Latin alphabet was not designed for English and many words are spelled as they were formerly pronounced in some other language (French in particular). English like all languages, has both advantages and disadvantages. The greatest being that it was spread around the world to so many places that it is the world's favorite second language.
We are awful at teaching Foreign language in the US. Typically, a US student gets virtually useless "cultural enrichment" classes in grade and middle school, in which Sra Gomez pops in and says a few simple things and perhaps shows some filmstrips. Then in the Sophomore year, when the boys' voices are changing and the girls are figuring out how to spell their names with a y, and everyone is worried about being popular and zits, students get one 45 minute session in Spanish, French or some other language five times a week. This is repeated in the Junior year, so the total is 255 hours of instruction. No one learns any language fluently in 255 hours.
College instruction is not much better. If you are going to major in a FL, you will have to spend some time immersed in the language to become fluent. This is what is done in the Netherlands, Germany and Scandinavia, and some other places: most all of the faculty is at least bilingual, and HS classes in the sciences are taught in English (or German, or both). So it is usual to meet Belgians, Swedes, Norwegians, Dutch, Germans and Finns who speak English like native speakers. They have had around 1500 hours in school of exposure to English, and of course, probably a lot more listening to music and TV programs.
The Australians are worse at this than we are. Japanese public schools are awful at English,because the teachers speak a variety of English only spoken by Japanese teachers of Engrish. Those who actually become fluent learn English in "cram schools" after the school day is over. Cram schools are taught by native English speakers from the US, Australia, Canada, NZ and the UK.