Every time I mention changes like -4 base AD being completely menial and in effect for about three minutes of actual gameplay when an Ekko might be edging his kill or critical damage with four whole AD (which really translates to like 2 or so effective damage after armor tho), I get told that they're very significant and actually affect balance a lot.
Like with Vayne, she lost 3 base AD or so, and I mentioned that maybe her problem is chunking for 12% HP, flat, on any champion, under any circumstance without any sort of cooldown while most every other champion has at least a cooldown for true damage. I was told that it definitely makes a difference; I suppose I don't have the ranked experience to pull on to really say, I just don't think it's the answer to the problem at hand.
Anyway, the problem with most of the FOTM hate train champs are that they scale too hard. They don't get punished for building a tank build because they don't lose much damage to their competition, by comparison, since most champions just don't scale as hard.