Considering "slut" is what everyone who isn't polyamorous thinks of people that self-describes as polyamorous, yes.
Well, see, when I read this, I hope you're polyamorous yourself, because it means you're just making generalisations about what non-poly think of poly.
If you're
not polyamorous, you're either implying this is what you think of poly, or you're pretentiously excluding yourself from the word "everyone".
What I mean is, be careful about how you word such statements, because all three of the
literal interpretation of this sentence are offensive, and we can't read your mind to find out if you meant otherwise.
Another term I've seen used on poly blogs is "Ethical Slut", so yeah, they kind of are.
I'm surprised, because as I understand it, the Ethical Slut is just someone (most of the time celibate) who enjoys having no-strings-attached sex with various partners, while still taking care of not hurting their feelings, particularly by being upfront about it and not leading them on (and as a result, usually picking partners who are in the same state of mind).
I fail to see how it relates to polyamory, which is about romantic relationships involving more than two persons.