I can’t think of a more inviting target than a defenseless civilian ship ignoring all reason by sailing into an active combat zone without authorisation. Do they actually expect to just park up and do what they want, or expect their nations governments to come to their rescue? Good on them for wanting to help but this is the equivalent of a black man walking into KKK HQ to hand out some books.
I support Israel right to defend itself but well aware of a number of potential war crimes they have committed in the process - you may as well place a nice big radar reflector on top and save them the trouble.