Plenty of places extract bribes while being pro-development too (they just generally more directly ask for bribes - or ‘planning fees’ - and are more consistent with it, so that it actually functions).
Very few places with the type of control a city planning department has don’t end up corrupt.
The problem seems more that most San Franciscans are civically uninvolved. There are elections where less than a third turn out [1]. From what I hear, most voters never bother reaching out to their electeds.
So you have a naïve, ignorable centre. And vocal minorities who engage. Most San Franciscans are reasonable; the problem is they’re electorally irrelevant.
It's ironic, given that local issues actually tend to impact us more directly and immediately, while at the same time local elections are where your vote has proportionally the most impact (aside from a few unique situations thanks to screwy districting and the electoral college).
Which is unfortunate for the reasons you mention. And most people just tune out.
About the only people who will consistently turn out for those are local activists and retirees/local property owners, of which a big city has a proportionally small number.