Due to the water purity, Waldo Lake is largely infertile. Plus no permanent inlet streams exist, to feed nutrients into the lake. So, Waldo is incapable of supporting a high density population of fish. As a result, the angling is rated poor-to-fair.
Most of the brookies are skinny (under nourished), and only range from 8 - 12 inches. And there is a smattering of kokes still in the lake. Those are left-overs, from when Waldo used to be stocked...as are an occasional 'bow or cuttie.
By the way; stocking was halted, in 1990, thanks to the Eco-Weenie movement. But peeps are still allowed, to swim in the lake. Go figure. Peeps don't pollute the water? Any way...that's getting OFF topic.
At any rate...
The reason above are likely why, your friend said that Waldo has no fish. The fish are few, and far between. Plus, they're easy to find, on a 7,000 expanse of open water.