As someone else has stated: The best fishing can be found where you live. I grew up and lived in PA for 25 years and had very good fishing for trout, smallmouth bass, large mouth bass, pickerel, sunfish, blue gill, and crappie, and fished New York's Catskills many times before leaving PA.
I then went to fly fisherman's purgutory, South Dakota, and found excellent large mouth bass, crappie, walleye (a ball on a fly rod), northern pike, and very good trout fishing in the Black Hills. Couldn't stand more than one year in SD though.
Montana was my next stop for 12 years. I loved it. Great trout fishing (unfortunately, it spoils you and make regular good trout fishing seem to be poor fishing), excellent northern pike fishing (with pike up to 40 pounds on the fly), really good smallmouth fishing (that very few Montanana take advantage of) in eastern Montana (the lower Big Horn is tremendous smallmouth fishing), very good largemouth fishing, good whitefish (yep, they are a ball to catch in February and early March, especially when they run to 5 pounds or so), and the ubiquiitous squawfish in the middle and lower Clark Fork.
Then on the my current home state of Washington where there is steelhead, coho, kings, chum (love to catch the large (15 to 15 pound), fresh-run chum on the Skagit in November, pinks in the odd years, trout (unfortunately most of the good trout fishing within 5 hours of me is in lakes), smallmouth bass, and some very fine largemouth bass fishing within 15 miles of home (with virtually no fishing pressure).
Ah BC........ Steelhead, salmon, and some tremendous trout fishing in the rivers in southeastern portion of the province, not to mention the Kamloops lakes.
Which is best? It depends on the time of the year and the species you are chasing.