One could argue that the increase in hardware performance of computers has led to the art of software design falling by the wayside. Horribly inefficient software runs because the hardware performance hides the truth under the hood.
In practice it seems more complex than that — but I have experienced a softer version of that idea in practice with my own work. Performance does matter, but it isn’t the only factor.
Your point on inefficient code stands, but there is far more at play than mere "programmers aren't skilled enough" and "imagine the possibilities!"
I'll wager a true Mel would not be an easy thing to reoccur nowadays.