The vergence-accommodation conflict exist due to VR headsets having a fixed focus (~1.3m on Quest2). When a virtual object is close to the players eyes, the eyes will rotate inwards and try to focus on that object at its virtual distance, which causes a mismatch between where the focus from the headset actually is and where the brain expects it to be. This will lead to nearby objects being blurry.
Question: How many people actually suffer from this and to what degree? Can you train yourself out of it (e.g. closing one eye to remove the conflict)?
Should be a thing for most people unless you are older in which case your eyes often lose the ability to focus very close (farsightedness) and then VR will work perfect for you.