I studied in 1988-1999, and these stories may be true for Soviet elite education, but not for average Ivan. I personally studied at a school with advanced Physics and English (our teachers after graduating from uni went to Minneapolis for a year of practice). But maths had nothing close to what's described in the article or comments here. No witty simple problems, just boring theorems, then simple tasks to solve.

I did see those witty nice problems in journals and special math tasks books, but that never appeared in our lessons. That was boring like hell. Well, ...at least it wasn't dumb, we did take logarithms, derivatives etc.

But if you take an average Russian, they can't solve a simple proportion problem: say, income tax is 15%, you paid $450 of tax, how much net salary did you get? The answer is easy: 450/.15*.85 (then do it on calculator), but when I did this calculation with accountants from vocational college, they were stunned and didn't get how I did it. I'm not exaggerating a bit.

So those people were either from elites, or nostalgic.

On other courses in Soviet/Post-Soviet school.

Russian language focused mostly on orthography, punctuation and participles. Like if British school focused on spelling "coloUr" or "emphasiSe". The examples of good style were only 19th century literature, especially Tolstoi's suffocating long sentences.

Literature course is similar to what Paul Graham wrote about in his essays: old, boring and already unimportant literature, plus writing essays that must imitate literature critics. I think this was the most hated task at school, and it lasted all the way from 5th to 11th grade. Such essay writing is still obligatory till today in 2021, and I see consequences of it while teaching in a university: students write in unnatural high style, but have difficulties conveying their thoughts or selecting proper evidence (few can distinguish between facts and theories). And that's in a good university -- I'm scared to think what less smart people write. This is not a "degradation" of modern ages, it's almost unchanged since Soviet times.

History course conveyed a Communist narrative, cherry picked facts and asked you not to analyze anything but to remember dates/years. E.g. a textbook on medieval history (6th grade), a paragraph on knights and their armor started with exactly this phrase: "It was not easy for peasants to fight even one feudal lord." (then it described the armor). The entire country of Grand Duchy of Lithuania (at the time it was also called Lithuanian Russia) was omitted, except for being shown on a map. Because it was embarassing to compare that country with Russia under Ivan the Terrible (who became an icon in Stalin's age).

Geography was interesting to me, but when I got to Wikipedia in 2004 and started reading on languages and nations, I saw how much was missing from there.

Biology was a simple and rather boring literature, and the home work was to read a paragraph and be ready to retell it. Most students would simply learn them.

(Actually, with mediocre English teachers that was the case as well: read a text, called "topic" and retell -- and the teacher saw students telling the text learned by heard, but didn't care.)

So, to conclude, math in Soviet elite education was good. Other courses were probably reasonably good, because those elite schools for talented also attracted good teachers. But the average school was of much lower quality.