As stated by a Conda maintainer in https://github.com/conda/conda/issues/8051#issuecomment-1549451621
their official position is that they know the old solver is slow and that is why they put effort in allowing the libmamba solver to be used in Conda.
To install:
conda install -n base conda-libmamba-solver
at which point you are free to use it once, e.g.:
conda install tensorflow --solver=libmamba
or set as default solver:
conda config --set solver libmamba
It usually solves in seconds.
For more installation info see: https://conda.github.io/conda-libmamba-solver/getting-started/