What has filled the role of flash for commercial websites is native iOS and android apps, which still somehow end up being way larger than a flash payload and also drain battery faster.
The truly magical bit of flash though was the small scale culture of making tiny little once-off things to share for the love of it, for free. Hacker culture, if you will.
In the flash days, you could make a little toy for fun as a 10 year old kid without a credit card, post it on newgrounds for free to let others see it, brag to your friends, and feel good. Now, you need to buy a macbook ($1000) and apple dev account ($100/yr) to be able to share your dumb joke with your friends at school.
No wonder young kids instead use the even more closed roblox platform to make dumb jokes rather than building iOS apps.
> This kind of superfluous interactivity is still possible with javascript/etc, but it seems to be less popular and is more likely to gracefully degrade
I'm sorry but— do we live in the same planet??
Either you only browse websites you find on marginalia.ru or there's no way you're possibly serious about this.
By my estimation, 90% of websites work better with all javascript disabled (by works better I mean they displays the content legibly and doesn't waste my bandwidth or CPU time with superfluous nonsense). 9% need first party javascript enabled. 1% need more.
Here's a short clip of me browsing the top results for pecan pie recipes: http://0x0.st/HJUU.webm
I chose this example because I think it's relatively representative of normal web browsing without a techie/retro bias, but the same demonstration works with links from HN too. All of these pages are rendered with javascript disabled. Most websites behave like these. Websites that need javascript, like youtube or various social media sites (including github, the only site presently linked on the HN front page that needs javascript), are a small minority.
The way some people used to make entire websites as flash apps that would bring old computers to their knees is not something I miss. Websites that should have just been static html, like a restaurant's website for their menu, were getting turned into monstrously inefficient interactive nightmares that wouldn't even load at all if you didn't have flash (which btw, broke constantly with Linux.)
This kind of superfluous interactivity is still possible with javascript/etc, but it seems to be less popular and is more likely to gracefully degrade (usually the relevant content still displays even if you have JS disabled.)