I don't think that's funny or a valid comparison.

Dogs aren't even the same species. It's not immoral to be afraid of them and having PTSD because of negative interactions with a particular predatory canine species is very normal.

Hopefully service robots won't be very far into the future. I don't want to discriminate against blind people. But I really don't think there is a problem with not being okay around a particular set of non-human species (alligators, hornets, lions, coyotes, dogs, bears, mosquitoes, ...)