No, a whole bunch of work was (hypothetically) _not_ done to verify if they were supported or not. I'm not suggesting that it's a good thing, I'm suggesting that laziness, sloppiness, or a simple oversight are just as plausible as malice.

It is _less_ effort to say "We support these specific platforms, and rather than doing actual feature detection, we'll just load a bunch of polyfills to make it work on anything else".