I don't disagree with you. The targeted companies i.c.w. expected no. of LTRs don't make sense. At the same time I also imagine a thought process behind the requirements like 'big companies' having to do with a fair level of abuse they want to prevent, i.e. not have (paper only) companies just to get 'a visa'.
Mate, your statement "A work permit can be cancelled anytime, and thus it has no expiry date" is incorrect as extension of the regular work permit is required at Department of Employment (just like the non b visa).
don't know about the palatial home in the middle of a rice field... but isn't the reason for 'selling assets in their home country' to avoid taxation? Where I'm from government is always very short of cash and actively looking for sitting ducks and easy targets 😉