Generally the Black Death is regarded as having improved Europe. At least if you regard the present as being generally better than the past.
Europe had just gone through two fairly good and comfortable centuries. At the beginning of the 14thc life was good, or at least comfortable for more than it had been. Even peasants had enough to eat. It was also, however, very hidebound, with all institutions of any sort extremely resistant to any kind of change or improvment, and most in need. Particularly telling was a population surplus, with declining wages and the ominous return of slavery. The Black Death certainly changed that, among very many other things.
It's generally regarded that the Renaissance was pretty much kicked off by the BD, at least in Italy, where Cosimo de Medici founded the family fortune that would change the face of Florence and eventually buy itself into most of Europe's ruling Houses. Cosimo was among the first bankers and bankers make money in good times and bad but very little in times when nothing is happening.
The BD, however, was not the only bad thing that happened in the "Century of the Scythe." There was also climactic change (Little Ice Age) with pluvial decades, where it rained almost constantly, to kick it off. There was the Hundred Years War throughout and I think one other bad thing at the end but I forget what. With or without the BD the Quattrocento was an interesting age to live in but not at all pleasant.