Oh absolutely, you can write perfectly fine software just by being considerate to what you're writing and never have to even consider optimisation. This is one

Oh absolutely, you can write perfectly fine software just by being considerate to what you're writing and never have to even consider optimisation. This is one area where premature optimisation becomes a problem for me; I know this, and I prematurely optimise anyway (though I am working turning that down a bit). For me, another widely held belief (although far less so than the root of all evil) is also somewhat the cause of this problem, particularly the issues you're talking about, this idea that if a library exists for something you shouldnt waste time rewriting it, which ends up with projects stacked to the brim with dependencies. Of course sometimes it is more efficient to use a library, I don't intend to rewrite perlin noise for example, but it shouldnt be your first choice I don't think.