I wish that Amazon would add a filter to the account settings. Each person would be able to block specific categories from showing up. This would apply to searches, browsing, and recommendations.
I have largely stopped browsing for books on Amazon. The massive influx of romance into other genres makes browsing a hassle. I have a similar problem with historical-fiction intruding into the history section. It became a huge waste of time. If Amazon would allow me to filter those out, then I would browse more. If I browsed more, then I would probably buy more. Instead, Amazon wastes resources showing me books that I will never buy.
Amazon may not care about my sensibilities or my time, but Amazon should care about making it easier for me to buy stuff. I pointed this out to Amazon's customer service. They didn't seem to grasp the concept.