Here's my verdict. […] But for the new generations and the general purpose forums, I think it's over for now. Maybe, and I hope it will be "rediscovered" in the future to become cool again.
Be patient. You had 70 posts in three months. That’s not uncommon for a new forum.
Mine had 32 (‼) in five months of the first year, 370 in the second, and 1,000 in the third. Sometimes I had more than twenty posts per day. My average is ~1,400 / year – and it’s a highly specialized scientific forum where only registered users can post.
Likely your ‘target community’ simply don’t know of its existence yet. Use social media and a link to your e-mail signature to spread the word.
PS: Asking for donations to run the site is possibly counterproductive.
Alfie (Helmut Schütz)