I don’t think this is true. Show me the numbers. I think Viki is still by far the more popular of the two, if DF is who you are referring to.
For DF yes. But for Viki, which I assume is your reference, prohibition is not expressly stated (please refer below).
Amen! I agree. I think the reason for not mentioning competitors’ site is encouraged and mostly done out of courtesy for all parties concerned. If it were out of conforming to rules, I agree, I don’t think that’s mentioned anywhere in the T&A of Viki’s site(unless I’ve missed it) but is on DF’s site (I admit I do access both sites, depending on drama availability). I also don’t think it’s fair to censor valid and polite comments in a discussion forum or anywhere comments are catered for.
In fact, a quick look at Viki’s T&A yields this, and which stated clearly there is no prohibition in mentioning third party sites, except that it’s on a basis of ‘Caveat Emptor’. But DF does state the prohibition while sharing the same ‘Caveat Emptor’ stance as Viki. If I’ve misunderstood the terms, let me know.
Viki’s stance on external links and Caveat Emptor:

DF’s stance on external links:
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But what I’m surprised to find is this, which doesn’t it negate the ‘international community subbing intent’?:

Overall, both sites did expressly state the limitation of use for 13 years and above.


All said, I am all for Freedom of Speech (and healthy competition), bearing in mind the usual courtesy that everyone should be accorded, just as everyone would wish to be treated.
SRC: https://www.viki.com/terms_of_use; https://www.dramafever.com/terms.html.
PS: I don’t know how to add spoilers in this discussion forum. If anyone knows, please advise.