I don't think any of the new development platforms have gotten even close to how accessible it was to make games in flash - pre as3 was the perfect combination of ease of art creation and programming
I haven't used RPG Maker in a decade, but when I did you had to import sprites, same with GameMaker. JS doesn't help you with art. Unreal Engine has a basic modeller but you have to use Blender which is quite complex for beginners
Flash was like an animated paint, super accessible