Behavioral Choice Architecture in Digital Finance: A Comparative Bibliometric Review of Nudges, Sludges, and Responsible FinTech Across Emerging and Developed Economies

Digital financial platforms increasingly embed behavioral choice architecture—nudges, gamification, and occasionally sludges—whose welfare consequences vary with institutional context. This study reports a comparative bibliometric and structured content-analysis review of 97 peer-reviewed articles (2016–2026) retrieved from Web of Science and Scopus following PRISMA 2020, integrating performance analysis, science mapping, and welfare-oriented coding of 90 full-text records across emerging (EM) and developed (DM) markets. Production grew sharply after 2024, accounting for 69.1% of output, with EM settings representing 56.7% of the corpus. Gamification dominated the field (57.7% of records at screening; 54.4% of primary interventions after full-text coding), substantially outpacing conventional nudges (17.5–21.1%) and explicit sludge or dark-pattern research (3.1–3.3%), and was 2.67 times more prevalent in EM than DM studies (64.0% versus 24.0%), the only EM–DM difference that remained statistically significant after correction for multiple comparisons. Co-citation analysis identified two intellectual communities—gamified digital-banking adoption and gamification motivation and continuance—both anchored in information-systems and service-marketing adoption research, while foundational behavioral-economics works remained outside the citation core. Behavioral effectiveness was documented far more often than welfare outcomes, and no retrieved study focused primarily on the exit stage of the digital consumer journey, a gap that persisted in a complementary search targeting sludge and exit terminology. These findings indicate that digital-finance nudging has developed primarily as an engagement-design phenomenon rather than a welfare-economics one, calling for differentiated EM/DM safeguards and urgent research on exit architecture and dark patterns as financial-services regulation begins to outpace the evidence base.