Mad Scientist isn't eternally overrated. I will fight you on this. It's still worth nerfing.
MC is not tame in standard. It is almost as overpowered as ever. The difference here is that Paladin no longer has the strength in its early game to support that kind of archetype competitively. If you re-introduced Minibot and Muster back into standard it would come roaring back.
I don't think people complain about Beast Druid synergy cards? I think people complained about Menagerie Warden because it was perceived as being OP. I heard no complaints about Mark of Y'Shaarj or Druid of the Fang.
Ever since they intorduced that 5 drop that turns into a 7/7 if you have a beast, people complained about them pushing beast into druid. It's not only beast druid, but pirate warrior, murloc paladin, secret hunter... so many archetypes. Thief rogue... There is always someone going "omg blizzard stop pushing this gimmick I want other cards". People are always complaining about this.
MC is absolutely tame in standard. You can't consider the power of a card in a vacuum. A card's power level in any given deck, especially MC, is reliant on other cards. We don't even see MC played because right now it's power level is far from OP. In wild it's power level has increased because of the nerfs though.
And mad scientist being
overrated is my opinion on what it was pre-standard, pre-nerf, with 2mana owl and kezan mystic. And it would certainly rely on it's statistics, I don't buy into the "omg 2 drop that draws and plays a random secret". It was often a very good on curve play but also a very bad off curve play and added inconsistency to your deck and could be a dead card if you drew your secrets out of order. Very
overrated because people rarely talked about the downsides of mad scientist and wholly focused on the god curve which is a very poor mentality to have imo. For that reason I think it was overrated. Very good in certain match ups (mage vs. druid) and bad or very bad in others (mage vs freeze mage, mage vs secret paladin).