These technologies can make life easier can let us touch people we might not otherwise. You may have a child with a birth defect and be able to get in touch with other parents and support groups get medical information the latest experimental drugs. These things can profoundly influence life. I'm not downplaying that.
I don't know of many evangelicals who want to deny gay couples their legal rights. However most of us don't want to call it marriage because we think that word has religious connotations and we're not ready to see it used in ways that offend us.
