My wife has lots of casual sex with various partners. We're in an open relationship but I do not consider her poly because, like your boyfriend, she does disconnect sex and intimacy and love.
As she's been doing this, I find that I'm less and less interested in her sexually. I agree with you entirely. For me, sex is an experience, a joy. The twitches and the shudders and the changes in rhythm reveal things to me about my sexual partner. It's a form of deep sharing, an expression of intimacy and safety and surity. When I was strictly monogamous, I would have sex with my wife and I would get some of this, but it was pretty clear from her feedback verbally and physically that she wouldn't. For her sex feels good and that's pretty much it.
When we have such very different feelings about sex, I find it's less about sharing and more about getting off. And if I wanted to just get off, I'd masturbate.
That said, I don't think this is damaging our relationship. Just as couples disagree about finances and housekeeping, we disagree about sex.
The greatest things about my personal journey into polyamory are 1.) The realization that no person needs to fill all of the roles of my formerly monogamous relationship. Indeed, people being so varied and unique, I don't think any person COULD do that and still appeal to me as a vibrant, lovable individual. 2.) That any disagreement or issue can be shared and worked on within our relationship. Being in an open relationship makes issues rise to the surface pretty quickly. Years and years of subtle resentments and irritations come to a head in a matter of weeks or even days when competition for time and affection are added to a relationship. It's been almost entirely positive for me since it allows and demands that we address issues quickly and honestly.
So while I suggest communication with your boyfriend like everyone else, I also suggest some earnest soul-searching about your own values and what it is that you're expecting and needing from him. You might find that he's simply too different and incompatible but you might also find a freedom in letting go of certain relationship roles because they don't need to be present in every partner.
My two coppers.