This standard refrain ("its just blobs and smears that I could do") is often repeated, but I have yet to see it actually acted upon (then again, maybe it has been acted upon, and the embarrassed critic burned the result after realizing the folly of his pretension).
However, I suspect you haven't really spent any time viewing Rothko's work, and consequently don't know his rather extraordinary use of color (sometimes inexplicable in its execution and effect), and the perspectives and peripheral imagery he created using gradations that change in shape and intensity depending on the light (which is why his work is best viewed in natural light that itself changes in intensity through the course of a day and indeed a season).
It might be a good idea to spend some time studying what you so blithely claim to be capable of reproducing before you commence with your project.
While I have not spent a great deal of time looking at Rothko's work (why should I when there are plenty of pieces by incredible artists to pay attention to?) I have seen originals at the Art Institute. Compared to that of hundreds of other artists his work just takes up wall space which could be put to much better use. Without a frame around it or being on a piece of canvas it would be easy to believe such works could be preparatory work on a wall prior to painting or plastering.
Modern art is not devoid of plenty of interesting, if not great, art and I like a lot of it. But Rothko's is at the bottom of the barrel and relates to real art as does Schoenberg to Beethoven. They are not in the same catagory. His would be the easiest to imitate of the name artists of the twentieth century. Particularly that which is one color on a canvas.
I think half the "art" racket is just being brazen enough to put it forward and claim it is art since few people are willing to stand up and call it what it is for fear of being called a "philistine". One of my favorite examples of such was the rags which looked as though they had been used by a housepainter tied around the columns of a federal building in Chicago. Another is the pile of junk being passed off as sculpture in a building across the street from that building.
Art without a spiritual diminsion is vacuous and the Left has destroyed diminsion in almost every area of culture. Culture as a creative and positive force appears to be dead in our day thanks to socialism and atheism. Now it is primarily a celebration of the ugly and the twisted.