I'm not aware of any socialist economy collapsing simply due to mass underemployment. Most socialist ex-economies collapsed primarily due to the effects of the end of the cold war. They were generally already devastated by WW2. It is by no means certain that a capitalist economy would have fared any better.

Not that it necessarily matters, since most "socialist" economies didn't really have anything like a basic income. The closest was probably the USSR, where everyone was notionally guaranteed an income, but only because everyone was guaranteed a job, and voluntary long-term joblessness was illegal.

The fact of the matter is that there has never been a country-scale attempt at implementing a basic income. Nothing even resembling a basic income has been employed in a country that didn't also have its economy devastated by war - whether civil, cold, or world. The small-scale trials of basic income have had either neutral or positive outcomes.