What the article doesn't mention, and that I have only anecdotical evidence for, is classes becoming easier. What may cause what is unclear, but probably it's a system so complex that pinpointing a single cause is hard
In that case a solution may be dropping grades altogether, exchanging them with some kind of written comment. This way "grades" can't be compared. Ultimately if you think about it, grades imply that knowledge can be measured, which isn't really something proven, and intuitively I'd say that knowledge can't be measured
