I did not talk about deformities, you’re the only one calling it that. I’m talking about the relation between posture issues/back problems/leg problems and feet which is medical fact.
It’s not always the case with flat feet, as it really depends on the gait (if you have a normal gait then problems are unlikely) and if you over or under pronante. A lot of people who don’t have an arch, also over pronate though.
You seem to have some kind of bee in your bonnet about this? Maybe people in Pak have weird superstitions about this? Maybe you were told you have a deformity?
It’s completely normal to have under developed arches (a decent proportion of the population do) but it doesn’t hurt to develop one and watch out for related problems that might benefit from insoles etc.