Yep, those are two examples of Lance throwing nice deep balls to WRs in stride. The pass to Deebo was not a great pass, IMO. Deebo was in between and ahead of the defenders in such a way that anything in his vicinity was going to be a catch. I have always thought Lance threw it behind Deebo such that another WR might have been tackled short of the goal line. The pass to Sherfield was also more of a crossing pass than a tear drop to a guy in stride, which are harder to throw. We've seen Purdy throw plenty of long crossers accurately (and that's also one of Lance's better balls, and what he hit repeatedly against the Broncos in the preseason). I've also got to point out that two of those passes were in the preseason, though a nice ball is a nice ball.  
There's no doubt Lance has the ability to make great throws. But again, he just doesn't make them often enough. And given that he's much less reliable on the more routine stuff, the fact that he's 30% better on deep balls just doesn't bear out in the longterm.