Fainter doesn't necessarily mean "less important": it may just indicate a separate channel-of-interleaved-information, sometimes skippable. (And, since comments

Fainter doesn't necessarily mean "less important": it may just indicate a separate channel-of-interleaved-information, sometimes skippable. (And, since comments are less rigorous and less-definitive than the code, code readthroughs often want to toggle between considering them, and not considering them.) Red doesn't necessarily mean danger or disfavor. Its use for removed-ranges owes mostly to longstanding use in editorial review (red pens), emphasis ([rubrication]), and as indication of stopping/ending (as in "discontinue this text") – without any inherent 'badness' evaluation.