Now my question is, why can these industries not increase the price of goods and maintain the quality? why is there an increase in price and then still the quality is being reduced. I have noticed this across so many other product in my countries market, not just this yogurt drink.
I know that this will not be so if my country has a good quality control unit, but even without that, why can these industries not act right and maintain quality, is reducing the quality of product while increasing the price not directly affecting their business?
As time changes things always change, and over time the standard of goods and services in the market also changes , not only in terms of looking at the price but the quality of products that is been produced now. These days I feel that government has not done enough in the areas of protecting the right of the consumer.
This is an oversight of everything responsible government, because industries should abide by the standard of every rules and regulations that is been set up by the government. This is because if the necessary guidelines and procedures, I don't think that there will be situation where a product will be produced in a less quality standard when compared to the standards of the country.
I don't think that inflation should be used to justify this type of moves coming from desperate and greedy individuals. Who is just out to making money by all means this is because the more you reduce the quality the more people run away from such a product.
The industries can take action. They choose not to. Because of information asymmetry, they can get away with it. Sellers have more information about what they are selling than buyers. Over time the poor products displace the good products. Consumers can't tell the difference.
They replace actual ingredients with less expensive fillers, tweak the recipe a bit. Most consumers are only aware of degraded versions after months of purchase. By that time the company had collected the margin. There are industry terms for this these days. "Skimpflation" when they reduce quality, "shrinkflation" when they reduce quantity. Both achieve the same thing: you pay the same or more, you get less value.

Anyway, Austria literally passed a law this year forcing retailers to label products that got downsized.

It is not a coincidence that there is no regulation. In many emerging markets these are the agencies charged with enforcing quality standards, but fail to do so. Such as underfunded, understaffed, or straight up influenced by the industries they're supposed to regulate. This is what is known as regulatory capture. The fox is designed the security system. Technically the government did put in place the right guidelines, but who is in the room when they're setting the guidelines?