Hey folks,
I hit this too. There was some more help in this github issue. It seems this is a numpy version problem (latest installed versions of numpy are causing it, but an earlier version does not).
Running this in the gtdb conda environment should solve it (this downgrades numpy to v1.23.1):
conda install -c conda-forge numpy=1.23.1
Even though that issue says this will be solved as of version 2.1.2, I put in a pull request to the bioconda recipe for the time being while we’re all still conda-installing things prior to when 2.1.2 is released.