Hmm, it doesn’t work for me via inaturalist.org either. That is a pretty complex umbrella with 51 subprojects so I wonder if that is part of the issue.
Big umbrella projects are not loading since spring, there’s nothing you can do until iNat as a website will be changed, so either reorganise the project, make duplicate as collectional or just wait, there’s nothing that could be done, but you can try to use less filters, like in an example of this thread: https://forum.inaturalist.org/t/large-umbrella-project-not-loading/23436
I’d remove those rules and just have no taxon rules there since it looks like you want basically all taxa in the projects. Those are four redundant filters on each subproject. I can’t guarantee that will help this umbrella project load, but it might help and it will definitely make the subproject pages load more quickly.