Well in a way it was also much more simpler, you had in DOS days a direct interface to the video memory and you most probably understood more accurately how the

Well in a way it was also much more simpler, you had in DOS days a direct interface to the video memory and you most probably understood more accurately how the whole operation worked. So developers could map the hardware in their head more easily, vs nowadays where you have in many cases at multiple layers of abstraction between the code and the computer, having to figure out cryptic black boxes like OpenGL drivers and what not that are difficult to debug and make it hard to understand how things work. Back in the day of course challenge was more not having widespread documentation and figuring things out as you went, especially with these pioneers.