Rally 3 class

[Daniel Popov]

the key in your post is past tense... Since few yers ago prices have gone up significantly...
So the price of a rally 3 is relative to gr N

But Rally3 is not relative to N4. In a lot of countries back in the day, the group N was a top tier car with which you could fight for overall victories/podiums. Now the Rally3 barely fights a Rally4 car.
Also with the N4 you could start on a low budget and step by step build it up to a top spec. With the Rally3 you are on 120 000 Euro from the get go.
So I don't think Rally3 replaces N4, it is it's own new group with it's customers.