Yes it's a technical limitation which he would not have chosen today. I agree.

In the silent era they had to work around the missing technology and that affects acting style, story points, the pacing, lighting, set design etc. This created silent film. To reverse those creative decisions you need to redo lot more than color and sound.

Even today when you shoot b+w movies and probably use color camera you light it totally different. Just simply desaturating the image does not work.