A friend of mine worked there (I was working at Rostix at the time). I listened to his stories and saw how things worked there, and I realized that the only thing you can reliably get at fast-food places is ice cream, and even that isn't always good.

In general, it's a pretty fair point. As they say here, "rumors" are often just repeated by people, but there are also some well-established facts. Then there's the comparison of McDonald's restaurants in different cities, which often differ significantly in quality, especially if you go back 5-7 years, when they were just being built. And of course, you shouldn't include major cities like Moscow, St. Petersburg, or Kyiv in the comparison (for example, about 4 years ago, Donetsk almost killed me with a breakfast at McDonald's while we were waiting for a bus to transfer to the Azov Sea). The comparison of how standards are followed in America and here is simply laughable (if you're interested, compare court cases here and in America about a purchased car with defects and the amount of compensation for moral damages alone; there's no need to even talk about material damages and court costs, as they are assumed to be included). And in general, it's quite a cholesterol-rich and unhealthy food that simply disrupts all processes in the body if consumed in large quantities.
By the way, as an example. At one time, my acquaintances' workplace provided vouchers for a certain amount to be used for meals at McDonald's (it's located on 1905 Street, in the same building, with offices and a bank on the other side). They stopped doing this after about 30% of the employees developed gastritis, stomach ulcers, etc., as a result of eating two meals a day at McDonald's. This is specifically about eating at these establishments, not just having a snack once every two weeks.
So, it's more a case of someone having an opinion and not being easily persuaded otherwise, because arguments from either side can easily be dismissed as "rumors." In my opinion, it's a disgusting imitation of the West, and even in our, unfortunately, traditional style (where they try to save money and cut corners), and it would be better if it didn't exist at all.