......I think maybe Honda concentrated too much on getting bonnet stickout / car length as short as possible, with max interior space on 2002 - 2008 model and moved the CAT to below the car. .....
Back in the dim and distant (last century) in car design/devt we genuinely never even considered people jacking the car up and cutting catalysts off the exhaust. Back then most cars had fairly large underfloor cats with relatively high precious metal loading and maybe a small metallic starter cat in the downpipe, basically down to the volumes required with the technology available then to clean up the muck.
Evolution of regs and standards, plus the tech to make raw emissions cleaner and durable close coupled downpipe cats (as Culzean says) for faster start-up etc. more or less removed the large underfloor items.
Having to combat the crims is just a reflection of more modern society I'm afraid. Consider the weaknesses of things like keyless entry/starting with the crims using relay boxes. You need to employ crooks to advise on how to make thinks scum-proof.
I suspect someone will come up with a way to steal the charge from EVs or charge stations, even if they don't simply have away with the cables.