Here is the Legco agenda item discussed
http://www.legco.gov.hk/yr16-17/english/panels/ea/papers/ea20170227cb1-574-4-e.pdf
The argument put forward in the paper:
"In recent years, the licensed[4] private car fleet has been growing substantially, a 13% increase between 1 January 2014 and 31 December 2016, being an average of 4.1% per year. As at end 2016, private cars accounted for 73% of the entire vehicle fleet. While electric private cars account for just 7.3% of the first registered[5] private cars in 2016, its rapid growth in the past few years has become a cause for concern in the Government’s endeavour to rein in the growth of private cars. Partly because of the advancement in the technology, electric private car manufacturers have been producing mass-market electric private car models with prices, reliability and driving performance that are increasingly competitive with those of conventional cars. For example, technological advancement in recent years has enabled the majority of electric private car models on the local market to be priced below $500,000 (with FRT waived). These electric private cars have a travel range of around 160 km or more after a full charge, meeting normal daily driving need of most local drivers. More manufacturers are expected to go down the same path to produce affordable models of electric private cars in coming years, leading to further increase of supply and market competition in the local market. This latest development calls for a good balance between promoting the use of electric private cars and stemming the excessive growth of the private car fleet, when considering the FRT concession for electric private cars after the expiry of the current waiver."
The minutes of the debate will come out here probably in a few months by which time it is too late....
Legislative Council of the Hong Kong Special Administrative Region - Panel on Environmental Affairs (Meetings)