Oda just wanted to introduce GB here. GB's "hype" was trashing 2 top commanders at the same time. That's insane hype, because nobody had done that, we had MF war where commanders were quite threatening, Big Mom literally running from a commander earlier in the same arc. It's unfortunate he used King/Queen like that but that was supposed to be the big intro moment.
Yonkou fanbase were praying Momo and the scabbards were enough to cause GB to leave, reality was it took the presence of another Yonkou crew for GB to finally back off. That's simply Oda's way of sending GB out after his intro without dehyping him 1 bit. Because realistically even Prime Roger wouldn't stick around for that by himself. So this said nothing about his power level.
I'm also expecting a cool looking panel in this chapter to send him off, maybe another one of him flexing his ability. It's the way Oda does things, he did this when Kuzan stopped Mingo, it de escalated without Mingo looking bad. GB apparently still has to be dealt with in the future he was never gonna have him be stopped here.