There is not without ray-tracing, unfortunately.
Everything is blobby because the scene representation that non hardware RT lumen uses is made up of signed distance fields- it doesn’t matter what they are, but they do not and cannot match the scene geometry. Post-process volume settings will let you include more objects in the scene, increase some aspects of the quality, and reduce noise, but only hardware RT can really make a close match between the game scene and the lumen scene.