There is obviously huge demand for scripting on websites. There is no one authority on what gets allowed on the web, if the existing orgs didn't implement it, someone else would have and users would have moved over when they saw they could access new more capable, interactive pages.

The 49MB webpage just shows what our priorities are. It shows the target audience has fast internet that can load this without issues. On my average home connection in Australia, I can download a 49MB page in 0.3 seconds. We spend time optimising for what matters to the end user.

Is the page actually done downloading 0.3 seconds after it starts? Or is it just (your Internet speed) / 49MB = 0.3 seconds?