U are actually right regarding your statements and I have actually learnt from your words.
I would say that if it was NOT adopted it won’t favour some people too. In both cases, some people won’t be in favour so why not just do it then?
Actually, the number of people who communicate with English Language is more than those who don't speak or type in English because English is one of the mostly used official Language.
There are people who can't speak English fluently but you see them typing their posts on musing with their lot knowledge of English Language. Some even make use of Google Translator to convert their natural Language into English Language.
The fact is that we have more of English Language communicators on musing than other Languages. It won't be of good help if other people start using their Language to share their ideas on the platform.
What do you think will happen if Indians, Philippines, Hausa, Igbo, Arabic and other language speakers start using their languages to share ideas, don't you think it may lead to a form of cheat for other language users?
Don't you think most people won't be able to answer questions unlike before because they can't understand what they language.
Spam does not need to be in foreign languages.
Accepted but there is likely to be more increase in spam if multilingual system is adopted.
is there an official post on Steem stating that English only will be accepted at the moment?
I guess this is where you are getting it wrong. Steemit is a decentralized social media /blogging platform built on steem blockchain. When you are making use of Steemit, you are free to use any Language because you are the master of your blog but in the case of of musing, it is entirely a different case because musing is only a question and answer platform just like Quora built on steem blockchain. This implies that typing with any language on your Steemit blog doesn't mean you can start typing same thing on musing because that's one of the don't of musing.