https://blogs.scientificamerican.com/observations/if-you-want-creative-solutions-keep-your-team-small/

An almost universal trend in science today is the growth and prominence of large teams and the receding presence of small teams and solitary researchers. To be sure some highly complex scientific research requires massive numbers of participants; the Nobel Prize–winning LIGO experiment that detected gravitational waves, for example, included over 1,000 researchers, as did the group at CERN that confirmed the existence of the Higgs boson (another Nobel-worthy discovery).

Although the motivation for larger teams is understandable, research in social psychology has extensively documented the benefits of small teams, which outperform larger groups on criteria ranging from efficiency to creativity and innovation. To understand the implications of the shift toward large, complex collaborations, therefore, is of fundamental importance for science and scientists; these are increasingly viewed as core engines of breakthrough ideas and innovations.