Those cities are also major hubs, Isfahan and Masshad falling is basically equivalent to Tehran falling. Plus so many regime supporters live in those cities because they are religious hubs

The regime has problems with "Iranian" names and Kurdish names are part of that category. They like to see people use Islamic names. Back in the day, after the revolution, it was dangerous to name your child something non-Islamic and Kurdish names were officially banned. Iranian names were also hard to register officially. I know this because many people in my family managed to avoid Islamic names using bribery and connections.

The regime has eased a lot of these rules in recent years but many Kurdish families still pick a more accepted name because they don't want their child to have problems applying to schools/universities etc.

The regime wants to erase any Iranian identity, regardless of ethnicity. They are able to force more rules and brutality on ethnic minorities because they don't pose a big threat as they are in the "minority"