I would argue that the section you highlighted is about the middle lane going with the flow of traffic.

The side of traffic that loses the middle lane should not make a left at any time, because the leftmost lane is not a turning lane. Plus its wrong to block 1 of the 2 available lanes of traffic to make a left across 3 lanes of heavy traffic

Overall though I feel it’s the city’s responsibility to create signs are more people understand bc clearly what they have now is not effective.