For decades, sustainability researchers have tenaciously insisted on transforming higher education institutions into more sustainable and inclusive campuses. Yet, as the 2030 agenda seems unlikely to be achieved, universities are struggling to meet the fourth Sustainable Development Goal (SDG 4) before the 2030 deadline. In addition, the post-COVID-19 era demands quality and inclusive education that entails care for students experiencing high stress levels. So far, most of the significant achievements are within the environmental or economic dimensions of sustainable development, but strengthening the social dimension is still one pending task. The importance of happiness to sustainability initiatives on campus, and beyond, deserves further research. To this end, this article offers insights into incorporating the sustainability–happiness nexus into sustainable universities to enhance the social dimension of sustainability. COVID-19 reminds sustainability academics and stakeholders that teaching technical and scientific knowledge is necessary to become more sustainable. Still, it is not sufficient to achieve the goals in the 2030 agenda. Providing inclusive and sustainable quality education will be reached when more sustainable universities consider happiness the ultimate goal of human development.