Honeybees are suffering from multiple problems including outbreaks of disease and parasites. Even without pesticide they would be doing bad.
Anecdotally bumble bees are a very common sight here. And I'm surrounded by fields that are sprayed often.
Do you have a source for how significant this factor is? I would like to believe it, but it sounds a lot like wishful thinking.
I'd also note that many native bees also have a much shorter lifecycle - they will be active for a very brief time at a very specific time of the year, when their target plants are flowering, and then they lay their eggs, which will remain dormant / develop slowly for nearly the full year, to hatch again at the appropriate time. This means that you can successfully avoid killing them by timing your pesticide application to avoid flowering plants. Honeybees, on the other hand, are active year round (though confined to their hives in the winter).
A larger threat mentioned in the talk to native bees was actually global warming. Many native bees operate in narrow bands of latitude, only going so far north and south. With the increases in average temperature, we're seeing the southern border of many native bee species move north ... but for whatever reason, not the northern border. I'm not sure why that would be (maybe there are plant species they depend on which spread too slowly?), but it creates a worrisome picture of their habitat being squeezed out of existence.