No one likes to be lied to. The internet and other forms of information delivery are probably the beginning of the end for such groups as JWs, unless they can play on that conspiracy theory fear. If they can refrain from too many of the more obvious and ridiculous false prophecies, they may retain those members who have been convinced not to "consider all things", or those who have been convinced that all other knowledge itself is evil.
Knowledge is the key, information is only part of the answer, as information is not knowledge. It's evident in how JWism is primarily an American phenomenom - information overload doesn't equal knowledge, but it makes an impression.
There may well be an increase in developing countries with limited access to "all things". Anyway, those concerned and empathetic can still continue to do their bit spread the 'word' about the 'truth' as they can.