I understand why people are upset because cars are a little "off" in terms of futuristic design.
But I don't think that it is such a bad thing when you consider that every car match the "styles" concepts that CDPR are doing with the game (Entropism, Kitsch, Neokitsch and Neomilitarism), and every style is fit for a very specific economic class.
I'm no lore expert, but from what I felt, I have some impressions about the society of NC that I like to share - to explain why there are a lot of "common" cars in NC:
A) Being a little more pessimistic than our real world - Cyberpunk 2077 is a futuristic dystopia, so the majority of population will be very poor. ;
That's why they'll probably fit entropism style - having whatever cars and augment as long as they work (necessity over style) - which is why entropism may be the most seen style in NC (I'm guessing) and the majority of cars will be a little off in terms of style for that reason, so we can be more imersed in this world.
B) Kitsch will probably be the middle class, formed by low tier corpos, gang members, people who doesn't have any real power, influence or money, but they're not as doomed as the poor ones, so they maintain a certain style even without real resources to back it up - just as real life broke middle class people that flirt with bankrupcy to buy things they can't maintain to impress people they don't like as a social defense mechanism, or to seek an opportunity to grow by influence - just like thugs keep some "tough" acting to send the message that they can't be messed up, gaining respect among themselves.
C) Neomilitarism that are the people who have power, influence and money, but aren't really concerned about showing it to the world, as long as their plans are going well, they just don't care, they have nothing to prove and no moral boundaries. They operate by some stoic ways, even if it's cruel. I guess that this class will be formed by top tier corpo and military. Their cars will probably be high tiered, but very discrete.
D) Neokitsch will probably be the high tier artists, rich people and politics, people with influence, money and power enough to set the desired rules, that all society should follow (in their point of view). That's why they'll probably use a Rayfield or some very high profile well designed futuristic cars.
So, based on that personal impressions, I guess that we'll see a lot of low tiered cars in NC, some of middle class tier cars, and rarely something like a Rayfied or Herrera.
We have to remember that in Cyberpunk 2077 there were a lot of corporate wars and economy is not really blooming in NC (Pacifica district as a recent economic failure, for example).
So that's why I find reasonable to don't have a lot of futuristic expensive buildings and cars around NC (depending on the area you're visiting)