I would say no. I know of one failed site that had been in business about 3 years and I dont think he made a penny off of it.
We are opening 2 niche dating site. The key is free female membership and if your city has a flyer. Mine is MemphisFlyer we post ads in the flyer every week. Make sure you site is populated cause know one is going to join a empty site.
People still make money in this niche. It's one of the big three niches: money, relationships, and health. All are passionate industries that drive a lot of businesses to the needs. Just because eharmony and match.com were setup a long time ago doesn't mean that you can't compete. Find your niche and start there. You just have to really dedicate yourself and you'll make money.