It depends on the level of English proficiency because Translators are not always accurate and ubiquitous for all languages.
Someone with a very low level of English proficiency can make use of Translators as they will help convey the message better.
On the other hand if the person has a basic understanding of spoken and written English with little errors, then the use of translators are not required
Although I am not a native Englush Speaker but I still do prefer to write my posts in English. But this is only a personal choice and I think that it is actually a good idea to make your posts in other languages as well.
I think it can be done on Steem without any fear of flagging. In fact it is more encouraged in some cases to share your content in multiple languages as it has the possibility of increasing genuine engagement on the platform.
I have seen several prominent users on Steemit do the very same thing. Using languages like Spanish and English or German and English for to two separate posts with essentially the same content matter.
English has become more popular than mother language . It has become necessary to learn English even if it is just to read blogs . According to a survey Content languages for websites :
I am not a native english speaker but I have been learning english together with mother language. So now there is no difference remaining between mother language and english . And this situation has been happening all over the world.
So now most of people who browse net are proficient enough to use english to write a blog. I assume that amount of people who post by translating should should be very less. Whatever content I want to write , I just write directly in english . Even if I get stuck in writing , it is at trivial points like not finding a proper word to convey what I mean to say.