You're badly misunderstanding where Wikipedia's current challenges lie.
The encyclopedia itself is the largest and most comprehensive ever created. Its accuracy rivals or exceeds any general-interest encyclopedia, and most special-purpose ones.
Wikipedia has gotten tremendous mileage out of ordinary contributions, but I suspect is starting to test the limits of what a crowdsourced project can accomplish.
Moreover, it's specifically the question of who finds it appealing to volunteer, or in cases, "volunteer", their efforts to the project, which is becoming a problem. It's been a problem for some time, but it's becoming more of one.
Several major areas are already political minefields, not only among actual and qualified experts within the fields, but of those who seek to control models and understanding for other reasons. Climate change is certainly one of these.
There are more mundane issues as well. Wikipedia is quite good on any events or facts based after roughly 2004, but coverage can become quite thin for earlier periods, particularly those which aren't popular.
There's the problem of sourcing material, especially as Wikipedia itself is online, but many of its primary sources aren't, at least not cheaply and legally.
The upshot: the problems Wikipedia faces today are not those that it faced starting out, at least not for the most part. Much of the real work and innovation is going behind the scenes. Part of that is technical, part is managing the emergent social dynamics of the project and its contributors.
It would be trivial for any other competing project to match Wikipedia -- it simply has to copy the content. For it to actually exceed Wikipedia, in accuracy, as an epistemic system, it would have to improve on the process overall.
That's a harder problem.