I speculate that there will be no difference between Shanghai and HK in the long run if Beijing forces the same rules to HK driving many foreign investors to relocate their main base to places like Singapore and maintain a small secretariat offices which they can cut loose when things get worse like the present anti-trust shame Beijing is campaigning targeting foreign car makers.
Beijing could have orchestrated a better election scheme with universal suffrage in place with favorable outcomes by placing various choke points on how political parties can be organized with nominees can only be appointed by political parties and/or place various limitations and check points to the elected official instead of acting irrationally and arrogantly stating Beijing has final word on selection of officials.
Despite my conditional support for universal sufferage in HK, I think we can't deny that the central government's offer was in the right step versus the present model, where the populace has even less say. So despite the central government filtering candidates, candidates would still have to campaign for the support of the populace, just within a few limits that the filtering process enables.
It's just unfortunate that it was shot down due to the preceding few years of poor social results and some attempts of Beijing to impose aspects of the mainland on HK such as education.
I'm not sure why you think Beijing would impose the same rules on HK as they have on the mainland regarding foreign companies, I'm not even sure if they've made noises suggesting that.
so I quickly checked