Following updated and extended measurements of the full angular distribution of the decay $Lambda_bto Lambda(to p,pi^-)mu^+mu^-$ by the LHCb collaborations, as well as a new measurement of the $Lambda to p pi^-$ decay asymmetry parameter by the BESIII collaboration, we study the impact of these results on searches for non-standard effects in exclusive $bto smu^+mu^-$ decays. To this end, we constrain the Wilson coefficients $mathcal{C}_{9}$ and $mathcal{C}_{10}$ of the numerically leading dimension-six operators in the weak effective Hamiltonian, in addition to the relevant nuisance parameters. In stark contrast to previous analyses of this decay mode, the changes in the updated experimental results lead us to find very good compatibility with both the Standard Model and with the $bto smu^+mu^-$ anomalies observed in rare $B$-meson decays. We provide a detailed analysis of the impact of the partial angular distribution, the full angular distribution, and the $Lambda_bto Lambdamu^+mu^-$ branching fraction on the Wilson coefficients. In this process, we are also able to constrain the size of the production polarization of the $Lambda_b$ baryon at LHCb.
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