I have been on both, I enjoyed my Apex cruise (3/2022 half capacity) more than my Beyond (1/2023) cruise, the ships had nothing to do with me enjoying Apex over Beyond, there were many reasons/factors on why...
As for the actual ship I preferred Beyond, she is about 90 feet longer, providing more space. Beyond has Le Voyage, World Class Bar, Mast Bar, Ocean view bar, plunge pools, better pool side cabanas, better sunset bar, better Martini bar...
I preferred the shows on Apex, food was much better on Apex (Beyond cruise in January 2023 was beginning of the now changed back food cuts..)
I actually have three more cruises booked on Beyond, mainly because of dates and ports of call..