Just as a clarification to your post re: color, Interlux Interprotect 3000 has always been produced in a white color. Interprotect 2000 is grey, but has recently introduced a white option.
I don't have lots of experience with barrier coats, but on my last boat - Interprotect 3000 was sprayed on the repaired hull. The final effect was a very hard and smooth, white epoxy - simulating a dull finish gel coat.
I do believe that most, if not all, epoxy barrier coats are distinguished by these similar characteristics, in contrast to anti-fouling paints. The surface is very hard, unlike the flaky layers shown in your photos. Be careful sanding however, if you're too aggressive, it's easy to sand through the epoxy.
True Blue . . .
sold the Nauticat