These are quite beautiful.
Reminiscent of Can G’MIC do those kind of textures? conducted in Software → G’MIC, May 2021 and months following.
To my mind, the Secret Sauce lies very much with the composition of the paints, how viscous are they? Are they absolutely immiscible or only relatively so? The paints’ viscosity remind me of those employed in silkscreening; those would be my starting point.
Perhaps — perhaps not. A very few sample points, irregularly distributed, and through time, driven by something turbulent, supplies a 2D radial basis function field, and that, in turn, warps a paint blob image. One could map the pole of a sphere to a rectangle, as with the UN flag, for a radial effect. Insofar as the turbulence is concerned, @David_Tschumperle roughly sketched as much in the thread quoted above.
More often than I generally expect, outcomes of extraordinary complexity and beauty arise from the simplest of processes. Recall the Mandelbrot map and various flavors of Julia sets, or Newton-Rhapson iterations and friends of those ilk.