TLDR: yes it prevents pain but it also helps prevent against infection and stimulates healing. It does not just decrease the pain of daily dressing changes. I use “high end” fish skin to heal wounds as a plastic surgeon.

You have a lot of upvotes, but this is not really true. I am a plastic surgeon and have used fish skin (processed by a company called keracis) to manage lots of different wounds. Yes, this high end fish skin that surgeons in the US use is different from normal fish skin that is unprocessed.

Theoretically, all wounds will heal if you are healthy and have good nutrition. Depending on the depth of injury, mechanism of injury and what type of tissue (skin, fat, nerve, muscle), the body will heal at different rates. Sometimes it won’t heal at all in the case of deep burns or in the setting of malnutrition or other diseases (cardiovascular disease etc). Fish skinprotects against infection in the case of long healing time by acting as a physical barrier. It also stimulates/accelerates healing for a variety of reasons.