For me, the most important aspect is Flash being vector. That an SWF file uploaded via dial-up can still run at modern resolutions their creator certainly couldn’t export a video for. Unfortunate that so much Flash stuff never-did (+never-will?) release in SWF form (and hours-long content takes up a sizable chunk of data for exported video even with modern encoding).

This also has me thinking about using old software again, specifically a Macromedia variant especially as it is less bloated (install-wise) than less-dead editions. Though I continue thinking that it still might be better to use some new open thing like Wick Editor instead.

That and I also lean more towards untextured polygons, both 2D (Godot specifically, a bit clunky for some aspects but in-engine animation is possible) and 3D (Blender-first, put into Godot or something like Raylib). Though I lack ideas and have mostly been tinkering with specifics on workflow (shaders/materials and import process, 3-digit-hex color palette) and am still wanting something better for semi-modular map editing.