I'll let you decide to what extent this applies to RV propane systems,...but I run a hot dog cart biz and have a lot of experience with these mobile propane systems and transporting them on various roads and how they tend to wear and fail.
While a hot dog cart is designed for a lot of extended use, it IS NOT designed to be part of a residential structure, so despite being resilient as a whole, they sometimes are fabricated with poor attention to protecting the fuel system from damage. I have seen many an abraded fuel hose, bad regulators, unsecured tanks, damaged valves and just poorly made (read that to mean Chinese) components. And I'm talking about a product made by profesionals who are actually handy with tools. Home-built systems are often Molotov Coctails with wheels.
I've also had my tanks refilled at many different places, some of which had barely trained monkeys who received minimal or insufficient training on how to do it. Most of the time when I smell gas coming from my cart or one of my tanks, its from a very recently refilled tank. The "technician" has usually not properly torqued shut the bleed valve
and this is where just a teeny weeny tiny bit of nearly inconsequential gas is slowly leaking. If such a tank is mounted outside, on the trailer tongue for instance, it is indeed a minor thing. But I've come home after a day of my cart or tank slowly filling my garage with propane and nearly been bowled over by how concentrated and thick such a small leak had filled such a large space in a small amount of time.
So with that experience, I say propane tanks should (if possible) be mounted outside. Their connections should be metal and not rubber, preferably. If propane tanks must be stored inside, ensure they are TIGHTLY shut AND secure from rolling or bouncing or otherwise able to impact other things or be impacted by them. If you find it necessary to use much force to turn valves and knobs to sufficiently tightly shut or if they "wander" and sometimes migrate from either closed or open,...replace those fittings. If you have rubber gas hoses, wrap them with something protective to prevent rubbing or wearing. (Attempting to secure rubber gas lines with zip ties is DANGEROUS and will actually CAUSE wear. Trust me on this. Don't ever do it!)
And if you do nothing else,...yes,...disconnect your tanks from your systems while in transit. Because you may catch a leak as you are connecting, and can safely address it. But if you leave everything connected and pressurized and TRUST that all is well when you next go to light something,...perhaps there has been something building up of which you were unaware or didn't notice. Also, any leak or failure is then likely to occur WHILE YOU ARE PRESENT and you'll be able to react quickly. If things are connected when you are not present, such as while focusing on the road in the driver's seat, or inside shopping at a store, whatever suddenly finally breaks and fails happens without you hearing, seeing or smelling it until far too late.
Now here's a tip to keep your paranoia from overdoing it. The smelly stuff added to gas so you can detect it by smell,...is synthetically manufactured and added to gas. Natural gas has no actual odor. And that chemical tends to settle toward the bottom of the propane tank in a slightly (and sometimes not so slightly) greater percentage than the gas at the top. Thus, as your large propane tank gets ready to run out, the gas gets particularly more pungent and foul than when first openned and used. This can lead you to think that maybe you have a leak because you suddenly seem to smell MUCH more gas. This is normal and a nasal cue that you have not much left and need to refill.