The digitization of academic practices has transformed how research output is shared and discussed, with academic social network sites (ASNS) like Academia.edu and ResearchGate emerging as pivotal platforms. However, their uptake and implications in contexts like Latin America still need to be explored. This study examines the emerging tensions related to using ASNS (Academia.edu and ResearchGate). As such, it offers a qualitative data analysis from 28 interviews with Chilean university researchers. It focuses on three emerging and overlapping tensions: the quantification of research via altmetrics, reputation building, and self-promotion. The findings underscore that altmetrics--despite providing a broader view of research impact--can mirror and perpetuate the problematic aspects of academic capitalism. Digital reputation, tied to high scores, conflicts with more qualitative aspects. The observed ambivalence towards self-promotion exposes a tension between the traditional scientific ethos and academic capitalism. Ultimately, this research unveils the multifaceted implications and paradoxes introduced by these platforms in the Chilean academic milieu.