Interesting video Julie, suppose it's turning over on starter as it's not fitted with any rockers etc. Shows how much oil stays up in the head.
I don't think there's any problems with cam in aluminium billy, most modern engines are likewise and car heads have no problems even in high mileage. You can see them up at 300,000 miles with no real problems.
Our issues on these engines come from oil condition only. People have historically not believed that you have to keep the oil at the service change intervals, but it's one of the most crucial aspects of running them. They don't really give any issues with oil supply and condition adhered to.
It's not the gearbox (often sited) either, it's simply combustion byproducts entering the oil that prevents it working competently. An issue that's particularly present in running engine's at low use with the type of carbs and choke method used on these.