That's a very sub-par argument. "Why do we need soap if you'll get dirty at the end of the day?" (basically)
Card games are all about odds. With no neutral anti-combo card it's almost impossible to win control vs combo mu. What's wrong about adding a card to standard which will increase the odds of winning to control players (and not only control players, btw). No one's asking for an insta-win card.
Can you present a non Insta-Win Card that fits your needs?
Dirty Rat doesn't fit the need. It overwhelmingly presents Control players with an Insta-Win situation whenever player, almost nullifying the natural advantage of the Combo decks, in turn, placing Control in an imbalanced situation where they face no hard disadvantage against Combo, while retaining their heavy advantage against Aggro.
Wild mode already enables this to occur and only a heavy balance problem called Barnes overshadows it. You can build an what is an almost invincible deck, a highlander Warlock with Combo disruption tools. It has everything, excellent tools to deal with Aggro, enough removal to withstand Midrange, enough value to match Control and the tools to disrupt Combo (which only requires one or two card slots).
At the moment I play my midrange/ Controlish eggPaladin , and just had a game against an oddrouge, he had a good start ,and beat me . But I know usually I should be slightly favored. Next game we meet again and after a longer game with Mira’s element etc. i was finally able to stabilize. No one of us ( probably) felt like he was heavily favored,or had zero chances. Decisions , taking risk, and luck ofc, all that and more made those games... simply fun . Do you have The same feeling playing an OTK deck?
( I know OTK decks can be hard to pilot, but do you really feel happy beating an OddWarrior,or another OTK deck where you had all your cycle first? )
Of course I have the same feeling playing an OTK deck. If I enjoy the playstyle why wouldn't I enjoy it just because others have a reason for why they don't like it?
I'm also not sure what your experience is with playing OTK decks but it is generally vs aggro and midrange decks that your most skill testing games as an OTK deck come out. For many of these decks you have to decide first of all what your win condition is. Is it still your OTK? Can your deck win another way if you throw your pieces away for tempo (some OTK decks can do this while others don't do this as well, such as Mecha'Thun Priest)? If you need your OTK to win are there any combo pieces you can throw away or commit for tempo to stay alive and still pull of a win with reduced OTK burst or less consistency in the late game combo if you throw a less vital piece away.
I think you have it all wrong by looking for the most skill in an OTK deck by comparing it to control. OTK/Combo has always been meant to punish slow greed, so naturally it will always be favored over aggressive match-ups and result in fewer difficult decisions when not matched up against aggressive decks. I get a lot of satisfaction and feel proud of games when I am facing a very aggressive and threatening opponent and decide that I need to throw away combo pieces to change or completely overhaul my win condition for the game (I do this all of the time with my Spectral Pillager Rogue in wild vs things like Odd Pally, Pirate Warrior, and sometimes Odd Rogue & Even Shaman). It may seem to hard to accept that other players & playstyles achieve the same experiences you do (just with different match-ups), but believe me it happens. Hating on a playstyle doesn't suddenly take its skill-testing and/or enjoyable aspects away for other people.
EDIT: To turn your argument on its head I could ask if you stop feeling enjoyment for playing control when you get matched up against very favorable match-ups for your particular control deck? Does the existence of favorable match-ups for control make it so that control takes less skill and rewards you with less enjoyment? See how silly the question is?
Like I wrote, I know there is skill involved playing OTK decks, and I don’t want them away or a " I kill your wincondition " tech card. I just can see the point of people who play a Control deck and wonder if that’s actually fun, or rewarding if you triumph.
And to your argument, my deck doesn’t have any high favored matchups. I even take cards out if I feel they make a slightly favorite matchup even more unloseable ( no cubes or umbra) . And even if I had such a good matchup, it would feel rather unsatisfying playing it out.