Wow, "O" is definitely gender neutral and "iro" is too, so it should be "They" are an important writer
No. They means "Ők" while the avobe sentence is singlar "Ő" either She or He.
Well that's exactly what I'm saying. O is either she or he, it doesn't imply a gender. So in English you would say he/she so I substituted the word "they".
Obviously I know "Ok" means "they" I'm a dual citizen of Hungary.
Dual citizen of Hungary? Living in both Buda and Pest? :P
I would suggest to pick either 'he' or 'she' here. 'They' may be a good option for gendering reasons, but it's grammatically very awkward since it's a different grammatical person. And I think we're already busy enough with all the different forms that translate as 'you' in English.
"They", used as a gender neutral third person singular, is not yet standard English usage, although it may become so as time goes by (and arguably should).
I don't think the Duo folks can be expected to OK it at this stage. The Hungarian ő simply has no single word equivalent in standard English, and in the absence of context you just have to choose he or she at random.