Rubberseal waterproofing on inside of hull

I just purchased a 1980's 14'6'' Starcraft Jon boat. The previous owner coated the inside of the hull with something called Rubberseal (web address below). Anyone have any experience with this product? What is the long term outlook on keeping it on there? Does it do any good in keeping out water?

https://www.rubbersealtm.com/

If I had to guess, the guy who added that stuff, had a leak he may not have been able to find so he coated the entire boat to be sure he got that leak and any more that might show up. In my experience, trying to seal leaks from the inside is not the best method. When you do that, the water has already gotten in the boat and will find a way to get through the patch, usually running between the coating an the hull until it finds a weak point and comes through.
If it’s not leaking now, you might just leave it alone. Removing the Rubberseal will cause you to have to repair whatever leaks the coating is covering up. Long term, fixing the leaks correctly is probably the best way to go.

Granted they waterproof the boat from the wrong side, but my only concern would be exposed to the sun delaminating that material. I think it would last longest on a freshwater boat that is trailered. IMHO use on a saltwater use, moored boat ... wouldn’t last as long, as any saltwater ingress into the seams would probably exacerbate the delam of it. As long as it looks good - don’t worry about it.