At the moment, Apple Maps seems to have a more thought-through design for public transit than Google Maps. Which is to say, transit view in Apple Maps is either visually clean and uncluttered, or completely nonexistent, depending on whether they got around to adding your city. Clearly a lot of by-hand design work goes into it, which isn't a very scalable approach.

On the other hand, transit data in Google sometimes appears to have been munged with no human intervention and never received even a cursory check by a graphic designer. For example, turning on Transit view in downtown Toronto will show a mess of ungodly rainbow spaghetti which is meant to represent the streetcar system. There are lines on non-revenue tracks where no streetcars actually run, lines on streets that don't have streetcar tracks, random artefact lines that appear and then vanish two blocks later, and lines drawn diagonally through the middle of High Park where there is no street at all. Somehow, the data behind this spaghetti is diligently updated year-after-year (e.g. the new Cherry streetcar was added in 2016) without anyone involved in the process noticing that the results are hideously garbled.

It also took them about a decade to realize that the SkyTrain in Vancouver is a rapid transit system.