In the Victorian era, drug use was not nearly as stigmatized as it is today, but sexuality was deeply hidden. You didn't dare talk about your sex life, but use of opium for purposes we'd call "recreational" was commonplace.

People are becoming more tolerant of minor drug indiscretions (cocaine is a nasty drug, but he didn't use it as an adult or let it become a habit, so I'd count it as a relatively minor issue) because society was at an extreme of intolerance on that issue, but I don't think that's a general trend in social acceptance of error.