I suppose to some I am not a collector, because I use all of my decks or have used them at one point. But to others, with currently close to or just over 100 different tarot/oracle/card decks, I am.
I didn't intend to become a collector, but I cannot say no to certain decks. It's either their art or theme that makes me want to work with it. Some, like the Dark Fairytale tarot, I quickly find do not live up to my expectations of it. I'll usually keep them just in case one day I find it more to my liking. I've sold decks before, and regretted it some. But from time to time heavily consider selling a few of the decks I know I never really liked once they were in my hands.
I think there's maybe two decks I purchased with zero intention of using, though I may read with them one day. Neither were expensive, so it was an easy decision to have them a part of my collection. They're super niche type decks- the Welcome To Nightvale Tarot being one.
There's only one I purchased when it was OOP- a Russian version of the Victorian Romantic Tarot. I'd intended to keep it unopened for value but couldn't help myself as it was the only copy of the VRT I own. Glad I did. I'm not someone who buys decks for their future value and the OOP ones I own are only special to me in a personal way, not because of their OOP status.
Of course I can't use all my decks all the time but I have become a regular member of the Deck of the Week group here which has helped me begin working again with decks that I haven't touched in a long time. It's a great way to help you sift through a collection if you don't like having a particularly large one. By the end of the week I've either reconnected with an old friend or felt more confident that we've gone our separate ways
My only concern about my collection is finding better storage... Sadly my grandmother's dresser I've been using is quickly running out of room.
Probably another sign I should either downsize or begin storing my more "Collection" suited decks elsewhere for the time being.
Long story short I don't think people are defined by their collections unless they want to be. I like to think of myself as a reader first, with a wide variety of tools available for both myself and those I read for. I have some clients who like me to work only with angel themed decks for them, others who like darker themes. I have a friend who won't let me leave home without my copy of the Wild Unknown Tarot