This question of mine started shaping in my head first while I was looking for the most fundamental answer for the speed of light's value and its property of being the limit.

I have convinced myself that it's due to the structure of spacetime, or in other words because the spacetime interval is expressed as $ds^2=dx^2+dy^2+dz^2-c^2dt^2$ which is not Euclidean (for the limit property part) and has the value $9\times10^{10}$ in front of the $dt^2$ term (for the value part).

So from this conclusion, and by knowing the fact that the coefficients of those coordinate terms can change with a "curvature" in spacetime, I wonder if the speed of light can have some other value in different curved regions in spacetime.

I don't mean it as differing between different observers in that same curved region but as differing between different observers in different regions with different curvatures.