Suggestion on tag clustering visualization
Instead of clustering, association rules is likely to be much more appropriate on such data.

Nevertheless it's obviously possible to treat cooccurrences as a similarity measure and cluster this for example using a variant of hierarchical clustering (for similarities, not distances!) Or by transforming the similarities to distances. You can also try to treat these as affinities for tSNE or MDS, for example (again, your usual library will likely not just work, but you will need to write some code yourself), but it's probably much easier to simply visualize the cooccurence matrix as a "heat map", after arranging similar tags close to each other with hierarchical clustering.