Most of the "badness" people associate with these, IMO, are due more to the fact that 1. in recent times they are inhabited by less well-off people 2. they usually need to be washed or painted, probably because they are inhabited by less well-off people who don't make it a priority 3. to the extent they are seen as crime/drug dens, that's because they have a stigma/are in disrepair so only poor people want to live there. It is possible for them to be nice, even moreso if they are new (and not poorly maintained, 60 years old). See https://en.wikipedia.org/wiki/Zelenograd as an example of a city with this style (go to Google images for more pictures). The whole city is like a park.
From an urban planning perspective, they have a lot of benefits. People can actually end up with a lot of green space in between buildings. They make it easy to set up bus or train-based public transportation, with walking a viable way to navigate toward a hub. The density creates obvious economies of scale in other areas. From a cost perspective, they are inexpensive to construct because of the economies of scale. The article mentions them as one of the few building styles amenable to mass-production/assembly off-site.
Probably my main gripe is that they are not often 'mixed use' and could perhaps do with shops on the first floor, though this is partially an artifact of the economic regime under which they were mostly built.