This is not specific to Crypto, but security. Also, the comments on how certain exploits are avoided on Instagram remind me of some ideas present in Edward Platt's (in Building Consensus Through Deliberation) observations on how information moves through groups of different sizes.
They didn’t prise open a locked window at the back of the building - they knocked on the front door and walked in. They did things that you were supposed to be able to do, but combined them in an order and with malign intent that hadn’t really been anticipated...
...Much like moving from Windows to cloud and ChromeOS, you could see this as an attempt to remove the problem rather than patch it. Russians can't go viral in your newsfeed if there is no newsfeed. ‘Researchers’ can’t scrape your data if Facebook doesn't have your data. You solve the problem by making it irrelevant.
This is one way to solve the problem by changing the core mechanics, but there are others. For example, Instagram does have a one-to-many feed but does not suggest content from people you don’t yourself follow in the main feed and does not allow you to repost into your friends’ feeds. There might be anti-vax content in your feed, but one of your actual friends has to have decided to share it with you. Meanwhile, problems such as the spread of dangerous rumours in India rely on messaging rather than sharing - messaging isn’t a panacea