“Mind immersing in rūpa” means to perceive “value” in rupa, which is based on avijja. Thus “avijja paccaya sankhara…(kamma)vinnana” happens.
People tend to take the face value of things to be real (because of avijja). Therefore they are trapped in samsara.
As Lal translates from Brahmanimantanika Sutta (MN 49):
“Viññāna is unseen, infinite, and leads to the rebirth process for all. With viññāna, one cannot comprehend the real nature of pathavi, āpo, tējo, vāyo, bhūtā, deva, pajapti brahma, abhassara brahma, subhakinha brahma, vehapphala brahma, etc. (in any realm) in this world (sabba)”.
