The thing about driving over the mountains is that you never know what you're going to get. In the Summer, they can have construction going on that delays you up to an hour. In the Winter, the weather can be bad which delays you up to an hour. Now, it sounds as though the weather component would be a bigger problem. Historically, that's certainly been the case. But now-a-days? You are far, far more likely to be delayed by road construction in Summer. Snow removal is actually very, very good, which keeps roads open. On top of that? We just don't get snow like we used to.
I remember driving over in the 90's where the roads had to be carved out of massive amounts of snow. It would be piled on the sides of the road so high that it towered over you. It was wild. And more than a little scary. But that rarely happens now. Sure there are days that the mountains get loads of snow... but it's just not the problem it once was.
Today's drive over the mountain was just... pretty... as shown in these shots taken from my dashcam...
There was only snow on the roads at the top of the mountain pass.
Not that this stopped some people from driving ten miles under the speed limit on essentially clear (albeit wet) roads. Because of course it doesn't.
That's something you can count on regardless of weather.