For one thing, so many people cry wolf when someone misclicks, lags, misjudges, is countered, or is camped. Since so many players refuse to actually look at the situation with a clear mind and actually weigh their options, so many int reports are dismissed. The system learns as it judges, so people who are actually inting can take advantage of what the system learned (that most reports are false), and can get away with it. The only exception is if the inter is obvious about it (runs it down mid and dies 23 times to the same enemy in ten minutes obvious).
Flaming is more straightforward. The system knows when someone is cussing someone out, using derogatory slurs, or just being a total prick. While there is a lot of doubt when there's an inting case, toxicity cases tend to be very black and white.