Quote to emphasise.Part of it is the small sizes of maps.
But I think some is because they have balanced all the terrain types and standardized the adjacency bonuses. Everything is so balanced that it doesn't really matter what terrain you have (with obvious Civ preference exceptions).
I know they wanted to eliminate lots of rerolls/restarts before playing a game . . . but the reason players were rerolling was because they were trying to get unusual start positions. They have eliminated the need to reroll . . . because any start is just kind of the same as the next one.
Actually, I made this observation back in Civ6 (and posted about it here on Civfanatics).
My analysis then was that in order to make the game more multiplayer friendly, they had equalised the starting positions.
Now they have continued this trend to reduce re-rolling.
The big problem is that when everything is equally useful, nothing stands out.
As a result, the player feels less frustrated, but there is also no longer the euphoria of finding the optimal settling spot and rushing towards it to be the first to settle a city.
On the other hand, there may be enough natural wonders scattered around the map to break up the samyness.