My idea is to "coat" all of the seams and seals of the RV with the coating so there would be no possible way for water to enter.
That might be a semi-effective short term solution. The nano technology coatings are probably going to be more in use as the technology matures.
A couple of things I see here are: Why would one use these products when there are time-tested materials in use that are 100% effective? Why is there a huge shift to adopt products that appeal to ease of use or replace processes that involve work with processes that appeal to convenience?
My guess is that the whole world is becoming lazier and looking for short cuts that don't involve any work. That people hire me to do the simplest tasks like changing light bulbs reinforces this belief.
There are more than a few posts on the Forum about folks wanting to apply a coating to their EPDM roofs. The actuality is that the EPDM itself, seldom leaks. It is the holes created by vents, antennas, fasteners, etc. that provide leak points. If those areas are adequately sealed, there won't be any problems with leaks.