It wasn't so easy servicable, 23 miles per gallon can be achieved only with best petrol (good luck finding that in USSR) and overall quality was suffering from a number of things: quality of spare parts, drunkennes of conveyor worker, altering of main design to make it cheaper...
And besides, _soviets_ per se wasn't ahead of time, since Lada/Zhiguli was produced on Italian factory bought completely from FIAT.
So if you want to praise engineers - praise Italians first.