Core XY didn't exist in consumer printers outside of Vorons that took hours to build. If all a new company did was take an obvious concept and make it accessible, then that just reflects poorly on the previous market leaders.
Vorons are not consumer printers. They are enthusiast DIY projects.
That aside, sure, maybe Bambu were the first to make an affordable core XY machine. But, outside of China, we still don't have an affordable core XY machine by this definition.
So Bambu were the first Chinese company to take advantage of cheap Chinese manufacturing to stop making crappy Prusa i3 clones, crappy other things, or v slot Bowden crap (Ender 3, etc.).
They were the first to "clone"[0] some existing core XY designs and make a polished and affordable product.
Cool.
I am not saying its a bad thing, but do we need to applaud it when China repeatedly undercuts the rest of the world by not playing on the same playing field?
[0]: I say clone only because many of the "clones" Prusa complained about so much were only visually similar to the uninitiated and were otherwise quite distinct (and also much lower quality). The Bambu core XY designs look a lot like other more expensive core XY designs of the time. But really core XY isn't hard, the hard part is all the fine details, which every "clone" maker has to deal with inevitably.
Again, the predecessors also looked like bambu printers, I don't know what to tell you. There are not that many ways to design an enclosed core XY machine.