Honestly, I think the first few chapters of Cross Account kind of stacked the odds against itself by making one girl seem too harsh and the other too perfect. The harsh girl wasn't "mean" to him for that long chapter-wise, but many readers already disliked her based on the first few chapters (although I like her character). I personally find the idol girl to be a bit boring of a character since she seems too perfect. The MC is basically designed so readers will have the ability to insert themselves into a world where a beautiful celebrity secretly thinks and acts just like them, which has apparently not caught on with WSJ readers.
Yuuna fills the ecchi harem romcom slot, and BokuBen is the lighthearted harem romcom representative. Cross Account is an odd love triangle due to which characters actually know the others exist or are talking with them, but it apparently hasn't been getting much in terms of TOC votes. Interestingly, every raw site I've seen the series on has a substantially larger amount of views than the other Jump series. However, since most are actively being translated to the current chapter, there are only a couple of series (Spring Weapon & Shudan off the top of my head) that this can make a fair comparison to.
To answer your question directly, I'd be pretty surprised if Cross Account isn't the first thing to go when more space is needed for a new serialization. Overall, I think that it's alright, but it's not really clicking with what WSJ readers want to see apparently. Thematically, it may have fit better with Jump+ given the prominence of SNS and stuff like that in the series. The art is really great though, I will definitely give it that.