...and yet every local you talk to will say without doubt "..pero aca se come bien!"
Note of optimism, things are improving. I had a pretty poor Vietnamese meal a few weeks ago in Palermo. 10 years ago I probably couldn't have even had a poor Vietnamese meal. I'd say Argentina is on a late development curve for food.
There is a political or sociological (nacional y popular!) element to this, where as with so much else the focus is often on raising the minimum standard (carne para todos) and importing tools and ingredients can be a limitation in terms of price. Sometimes the holy grail of carne para todos creates barriers (even if its just psychological ones) to creativity. There is a lack of understanding in terms of how to season food (there are more herbs out there than parsley!) what fish and shellfish are for (I don't really like fish beyond tuna, so I live in blissful ignorance) and what the spicey and sour parts of the palate are for (beyond bitter aperatifs).
Once again, be careful criticising. You will here "pero aca si, se come bien! I just smile and nod my head. In fairness, it's lack of exposure to alternatives at the root of that.
The staples are good, they are done well. I have no problem with a well made milanesa, and obviously a parilla - ice cream combo is a thing of joy. I like (gasp..shock horror) the local pizza, once you demosntrate the mental agility to understand it is not the type pf pizza you are used to and I like medialunas. Beyond that there are a few good stews (locro, carbonada) and empanadas but at that we reach the limit and disappear off into the blandness of vegetable tarts (unseasoned...herbless!) and poor imitations of italian dishes. Sorry, forgot honourable mentions to some regional lamb/goat dishes cooked on the staked cross and the cruelly tasty baby pig / lechon.
On the plus side, meat is very well butchered. Offal is popular, even pigs are well butchered in the right places, and you can find chicken of a good quality once you know where and you can save money and have a nice sat morning in the sun if you short at your local feria itinerante.
If you like Sushi your best hope is to convert to peruvian ceviche. In general (not always) Sushi has become low quality cheese ridden (yep, cream cheese!) gut rot. Never particularly fresh. You can get good Ceviche though, in this respect you need to tailor your expectations.
In that respect I am still kicking myself for allowing myself to believe I could get a good Vietnamese meal and allowing them to rip me off for a shitty imitation.