Probably helps that there almost 10 times as many 707s built as Comets, yeah?

At any rate, not on a per capita basis. There were 114 Comets built and 26 hull losses. That's horrendous. There were 1,010 707s built with 172 hull losses.

Although with the 707, it's worth pointing out that it had a much longer career and flew exponentially more hours than the Comet did, which was pretty much extinct by 1970. Once a bunch of third world operators got their hands on them, they started dropping like flies. It's also worth pointing out that more than a few 707 incidents were the result of terrorism and not the fault of the aircraft.