>If you can add a feature and it adds just 50ms to a 300ms pageload - it's unlikely anyone is going to block its release on performance grounds. And once the feature is released, there's no removing it.

Unfortunately this is happening, because compute power is cheap these days. It allows programmers to be lazy, take short cuts and not think about good software architecture. There is no economic incentive to optimise, because human perception won't perceive a difference and thus nobody complains. It's wild to think that we have basically supercomputers in our home and yet developers managed it to bring it down to a crawl with things like electron apps.