Following the seminal works of Feruglio, Ding and Liu on modular symmetries in particle physics, the Siegel upper half-space has emerged as a natural framework for constructing predictive models of fermion masses and mixings. As a higher-dimensional generalization of the complex upper half-plane, the Siegel space provides the moduli space on which modular symmetries act through symplectic transformations, potentially leading to strong constraints on Yukawa couplings and effective interactions.