nong fu, I don't think he was calling out any specific individual as cheating so much as giving examples of a perceived issue. Is your all time score high? Yes, but as you said you've been actively using the service for almost 8 years, of course it probably should be high.
To me at least, other people's scores aren't important. I study in my own time in my own way (which is part of why I like an online course as opposed to a physical classroom). At the same time there are others that appreciate being able to gauge progress against other individuals, and that competitive nature can serve as a motivating factor.
There are people who might see a leaderboard and “Point Press” to get to the top, artificially increasing their score by spam clicking answers. They might use a bot to do that considerably faster. I am not saying anyone here does that, I'm just saying that in a competitive environment there are some individuals who will do whatever they can to get ahead.
In the opening post, lifetime scores were highlighted, and I think that is a very poor point of comparison. If you take a look at the leaderboards for the past 24 hours, there are some individuals that have over 10,000 points in a 24 hour period. Is it possible? Yes. Is it suspicious? Maybe. I think that is what this topic was about. If there is a leaderboard (and a competitive environment), some degree of oversight might be necessary to keep everyone on a fair competitive field.
This all having been said, nóng fū, I admire your dedication.