  ALMA observations revealed the presence of significant amounts of dust in the
first Gyr of Cosmic time. However, the metal and dust buildup picture remains
very uncertain due to the lack of constraints on metallicity. JWST has started
to reveal the metal content of high-redshift targets, which may lead to firmer
constraints on high-redshift dusty galaxies evolution. In this work, we use
detailed chemical and dust evolution models to explore the evolution of
galaxies within the ALMA REBELS survey, testing different metallicity scenarios
that could be inferred from JWST observations. In the models, we track the
buildup of stellar mass by using non-parametric SFHs for REBELS galaxies.
Different scenarios for metal and dust evolution are simulated by allowing
different prescriptions for gas flows and dust processes. The model outputs are
compared with measured dust scaling relations, by employing
metallicity-dependent calibrations for the gas mass based on the [CII]158micron
line. Independently of the galaxies metal content, we found no need for extreme
dust prescriptions to explain the dust masses revealed by ALMA. However,
different levels of metal enrichment will lead to different dominant dust
production mechanisms, with stardust production dominant over other ISM dust
processes only in the metal-poor case. This points out how metallicity
measurements from JWST will significantly improve our understanding of the dust
buildup in high-redshift galaxies. We also show that models struggle to
reproduce observables such as dust-to-gas and dust-to-stellar ratios
simultaneously, possibly indicating an overestimation of the gas mass through
current calibrations, especially at high metallicities.
