No forum can compete or even come close to what Bitcointalk has achieved when you talk of forums about Bitcoin and Cryptocurrency
Why do you feel so ? There can be number of factors causing another forum to become more popular than this forum. Like suppose, the current forum owner makes some bad decisions because of which good members here migrate to another forum, this can be one reason. It does not matter if you are the first forum related to crypto. What matters is who is solving the problem of users in a better way.
No forum can compete or even come close to what Bitcointalk has achieved when you talk of forums about Bitcoin and Cryptocurrency, Bitcointalk is what Google and all into Bitcoin are recommending, all forums exist because of their niche, Bitcointalk and all the other forums are popular because of the popularity of Bitcointalk.
Before Google, there was dominance of Yahoo. They also never imagined that one day Google will be become bigger than them. So, never underestimate your competitor.