I have never really thought the meat here was that great. However this could be because i grew up on a farm, that produced grass fed meat, that wasnt full of hormones like most other countries - Unlike the americans or europeans or australians who come here and rave about the meat.
As for meat in argentina declining in quality and increasing in price - since the gov increased the export tax on meat and made it more financially profitable to grow crops, argentina went from being the worlds 3rd biggest exporter of meat to a net importer of meat this last year.
Thats is also probably why feedlots have increased in numbers, you can raise more cattle per hectare of land if you lock up the animals in feedlots - thereby reducing their exercise, which makes every mouth full of feed go into growth, and then feed with high yeilding crops (maize), pour fertilizer onto those crops to make them crow quicker, and keeping the animals off the pasture will also stop pasture damage and increase crop yield. The same thing they have been doing in the states and aus for years.
The feed lot raise cattle's meat also has a different taste, due to the change of diet, from grass to meal, and the meat has more fat in it due to the lack of exercise the cattle have. Some people actually prefer this marbled (lots of fat) meat, especially the asian markets.