Poly Haven add on is taking forever to load in Blender 5.2 and doesn't show anything when I try to install. I've followed the instructions properly. What is happening? 
When you first load up the addon it has to check and see if there is anything new to fetch. If it's the very first time then it will be busy downloading everything. I don't remember if there is a status or percentage thing when it's doing that. As you can see in your asset browser you have 8 new items so far to download. It will also periodically have to recache the thumbnails. This can take a minute or 2 depending on your system, internet speed, and how busy polyhaven's servers are. Since you don't have any categories listed on the left side of your asset browser it's probably the first time running it. It took almost 30 minutes on my system the first time, but I have a slow internet connection.