After seeing so many boats with bottle brushes and major lightning damage AND a major electrolysis problem I decided to avoid any electrical connection with the water and have been very satisfied. I replaced all thru hulls with marelon. That was about eleven years and over 25 thousand miles ago. Yes the 3/4" ones are kinda flimsy but are easily replaced even in the water. I also later replaced the saildrives with shafts. That was a huge project but certainly the best modification I've made. I included plastic discs between the shaft coupling to further isolate the water from any current flow. There is definitely not any electrolysis problem now.
Regarding lightning since the modifications...we've been in multiple major lightning storms with direct hits to the water very close and all around us. We've even seen blue flames shooting between our salon support poles but have not had any damaged electronics except masthead yet. In addition, once when hauled I was under the boat working on props during a lightning storm and got popped, probably not a direct hit, but it knocked me on the ground. After sitting in the mud a minute I decided I was already wet and muddy and should just finish the job...and lightning never strikes the same place twice, right? I had rubber soles too. Well, don;t believe that because I got popped again but worse this time about ten minutes later. I do hate lightning but don't talk to me about bottle brushes.