This
That would be true if it wasn't just an excuse.
An example is a game like mechwarrior 2, during development they discovered that unless the machine it was run on had a colossal amount of memory it would not be able to render more than one or two mechs at a time (by colossal amount I'm talking about 100megs or so, a lot back then). So they put their brains to work and found (invented something that didn't exist before) a way to do it and still managed to have the game look great (by the standards back then). That took
time and
effort, something a lot of developers don't want to invest in these days, no, not those. Big flashy graphics on the other hand...
Ironically if you look at the sales figures the Nintendo DS has sold more units than anything else combined and it's graphically on par with a Nintendo 64.
Good thing those other systems have really cool explosions and stuff because man, isn't sacrificing glitch-free game play for "true to physics" blood splatter art great.