The key is not doing the same thing everyone else is doing with their forums
There are still very successful forums out there, and there are forums with great search engine traffic as well from quality content.. eg searching for repair info for my truck I was always landing on the same trailblazer forum
There are still people who like to type, generally they are older people..lol
cater to them
oh also mobile use is very big... if your forums or website isn't usable on mobile, you're going to miss out on some traffic depending on your niche