Ugh, this old myth again.
Yoyos are meant to be unscrewed. End of story.
I think some of us stumble across preferences or have revelations after trying a stock bearings and pads anyhow. I don’t know for sure that I would have gone out of my way to find CTX bearings (I already liked KK) but having them come with the yoyo showed me that they’re great bearings!
“Pro” level yoyo is kind of a misnomer anyhow… you can get an allegedly “pro” yoyo as your first yoyo if you want. They’re readily available and not all that expensive in the grand scheme of things. They have to ship it with some sort of reasonable bearing because they cannot predict if the buyer is going to be a newbie or somebody with a stash of spares.
Offering a choice of bearing is a non-starter from a logistics point of view.
I think it’s overstating it to say that manufacturers match a bearing perfectly to a yoyo. I think there’s “some” thought put in, but in the case of OD it’s “We found this great bearing that we like, and we include it with all our yoyos”. In the case of YYF it’s “Any yoyo that’s at that ‘next level’ gets a CT or CTX; errthing else gets a SPEC, which is good enough…”. I’m sure other companies have other reasons for their choices (C3 Krown comes with KK because Shinya likes KK, for example).
Nothing wrong with “good enough”, mind you. As long as the yoyo is well-playable out of the box, they’ve done their job.