The balance of the evidence indicates that the health benefits of fish consumption, particularly omega-3 fats, far outweighs those concerns.
The article does mention that smaller fish often found canned are lower in the food chain and thus have less mercury, but I would think that you'd have to look carefully at each species, and the sourcing, and the packaging before you could really say the health benefits are worth it.
The author goes into lot of detail.
TLDR 1. Eat small fish like Sardines, Mackerel, Anchovies etc
2. Get your omega 3 index
3. Make sure your omega 3 to omega 6 is good
There's a lot of options -- salmon (I personally have salmon sushi at least twice a week), omega-3 supplements, a dozen other healthy foods.