Ok I actually implemented this in my fork of the General registry: General/generate_redirects.jl at master · jkrumbiegel/General · GitHub
Now links like https://jkrumbiegel.github.io/General/Makie or https://jkrumbiegel.github.io/General/ExperimentsManager (for a gitlab example) load html pages that just redirect to the repo stored in the registry. If it was desired, one could use a nicer domain and link structure like juliaregistry.com/Makie and we could link to those from here. The script could be run once daily or so to update, it takes only 40 seconds to run.