My wife and I did Crater Lake this year on September 10, 2022. The air looked a little hazy, but I didn't feel any smoke effects or even really smell it. The weather was great, but I hear it varies a lot up there. We parked near the lodge and did the whole rim clockwise. Overall, it was a great experience, so we'll do it again and take some friends! There's plenty of info on the ride itself, so I'll focus on our ebike experience.
There were a fair number of other ebikes, but we were definitely in the minority. As expected, we typically passed others going uphill and got passed going down. Traffic got dense at the rest stops, but everywhere else was uncrowded. There were a lot of people, but we weren't on top of each other. We rolled at around 9:30 and finished at maybe 1:30ish, or something like that. The parking lot was a lot more crowded when we left than when we arrived. The part of the road open to cars might be a bit unnerving for those who aren't used to it, but no one made us feel too pressured. That part was only 1/3 or 1/4 of the distance around the rim, and it went by faster, because we didn't stop and weren't looking around as much. We're pretty comfortable in traffic, but this part was less pleasant.
There was a fair amount of climbing, but we made the whole 30-something miles without needing our backup batteries. I was down to my last bar, though. We both rode Pedego Elements with street tires and 48v14ah batteries. We probably did about 14mph most of the time on level terrain and climbs. We mostly stayed under 30mph on descents. That's about as fast as my wife is comfortable with. We got passed a couple times by a non-electric tandem bombing downhill at maybe 50mph!
We live in SoCal, so it's a lot of driving to get there. We stopped in Mammoth a couple nights on the way up and Redding one night on the way back to do some riding and break up the trip. Both places have great paved paths to ride on. We wanted to ride Tahoe, too, but it was too smokey. We'll probably do a similar route next time.