Sure - the "race to the bottom" for hosting prices inevitably means there's going to be options like GoDaddy offering "a year's worth of webhosting for $5" which clusters 400 WordPress and Drupal sites onto a single RaspberryPi or similar, but you don't _have_ to go there.
I can understand if you're an open source developer who gets paid in Uzbeki Som or Nigerian Naira, the calculation of "do I spend a day or two putting caching in place" versus "do I spend an extra $50 or $100 per year on hosting" might lean very much the other way, but I suspect for the vast majority of HN readers, the prudent approach is "pay a hundred or two dollars a year for hosting before bothering to implement complex caching strategies".
