I think it is more the other way around in regard to being paranoid and seeking security. A basking turtle will quickly retreat into the water at the first sign of human movement. A python on the otherhand will bask until disturbed.
Not even a relevant comparison...
Snakes are far more paranoid than turtles mate. Turtles for one are true aquatic reptiles, basking on land for them is essential yet the most dangerous thing they can do in their life. Until you've encountered them in their natural habitat and dived with turtles underwater, you can't fully understand how bold they are. Snakes on the other hand rely on the chance of not being seen if remaining perfectly still until the last minute when camouflage has failed them, then it's either flee or fight.
A turtle underwater will readily approach and investigate a diver or sit and observe you as you swim past, over, around, whatever. I've many photos of wild turtles where I've put cameras in their faces and snapped a photograph of them, turtles don't get into a strike pose, hiss, get all defensive or flee when in their natural habitat, they've no need to, they have security 24/7 A turtle on land still has it's shell, so why does it flee when on land at the first sign of movement?? Because if it's prevented from entering the water, turned over, carried off into the scrub and injured, etc, it will die. Simple.
A turtle has webbed feet like a duck, useless for outrunning a predator on land, a shell on land becomes a cumbersome burden... In the water, a turtle becomes a weightless turbo powered streamlined jet. Try catching a turtle in open water without fins in a swimming contest. That's why they flee when disturbed while basking, to even the odds.
Another point, a turtle won't just automatically flee when approached, it all depends on the situation. I'm able to approach basking turtles (because I understand their behaviour) to within a couple of meters, if you don't make threatening body language or eye contact with them they don't feel threatened. Another thing you should never do is point at turtles, whilst above or below water, pointing at a turtle will cause it to flee, In the below photo I'm pointing at the basking turtles
but not looking at them. They remained perfectly still. Watchful and wary but they didn't flee.
I stood motionless here for 45 minutes in the sun observing their behaviour. During that time another turtle hauled out and proceeded to bask and watch me. Notice the deliberate positioning of the 3rd turtle, it's facing the opposite direction, they do this purposely to cover all angles of approach from land. If one flees into the water, they all flee, instantly.