I haven’t looked into this game beyond your description, but it does sound like a pretty weird model. Do you also have to pay for cards on top of that?
It’s not a card game, it’s an async autobattler. As long as all the characters are roughly balanced against each other, there’s nothing to be gained other than cosmetics (at the current state of the game).
People who claim “guys” is gender neutral would most often only count men when asked the question “How many guys did you sleep with in your life?”
Until I find a single person who immediately thinks of people of any gender at that question, I will not fall for the internalized misogyny of “‘guys’ is gender neutral” meme. (Same with “dudes” and all the other ones I’ve seen over the years. I’ve even seen someone say “bro” is gender neutral.)