https://en.wikipedia.org/wiki/2019_Hong_Kong_local_elections gives a breakdown of votes cast and seats won. The reason for the discrepancy between votes cast and seats won is the first-past-the-post electoral system used.
Seats were divided like this: Pro-democrats (81.00%), Pro-Beijing (18.58%), Non-aligned others (0.42%)
Looks like some democratic reform is in order even if HK is able to gain universal suffrage and keep the one-country two-systems indefinitely.