It's easy to make a mess in many things, and it's true Flash has it's share due to it's sheer ability to create beginners in the realm of digital experiences.
It's easy to make a mess in many things, and it's true Flash has it's share due to it's sheer ability to create beginners in the realm of digital experiences.
We obviously also cannot support any of Flash Player's DRM features, not for any particular technical reason, but because we (and likely Adobe) are legally restricted from shipping a pure-web decoder for that DRM. We probably could proxy to an Adobe-provided EME plugin, but that would require cooperation with Adobe and major browser vendors for a 0.01%er preservation use case. We also cannot proxy early Flash video as no browser appears to expose native/hardware H.263 or VP6 decoding, so we'll have to ship software codecs that will probably perform like hot garbage on HD video. Fortunately, I don't think there's a lot of SWFs or FLVs with HD video in those codecs anyway.
Flash also allows you to enumerate device fonts, which used to be possible on the Web but isn't anymore. I don't think anyone will miss it.
However, the web sandbox is so large and all-encompassing nowadays that all of the above seems like small caveats. The vast majority of Flash content that people actually want to use is either standalone movies (Newgrounds, Albino Blacksheep, other portals) or static websites (e.g. Homestar Runner, Homestuck). The big hurdles for that are AVM2, dynamic text & inputs, and Stage3D. All of those are almost-perfectly enclosed within the web sandbox. Most of the sandbox-prohibited stuff is necessitated by websites which likely either have executed a transition plan to web standards (and thus won't be using Ruffle) or are willing to put up with whatever extra wrappers or steps we require to make these old APIs work.
How about flash games? I bet much more time was (and is) spend on flash games, than movies or static websites alone.
But games are performance critical.