They can't though. Firstly NFTs and their image storage location are unrelated to tokens.
In regards to 51% attacks they aren't going to happen to Bitcoin or Ethereum.
For possible flaws, to put it in terms that technical non-crypto people understand, his arguments are like saying "well Heart Bleed happened and this could happen again thus all computers are unsafe and you can never trust them to be secure" which is technically true but that doesn't mean we should abandon storing our own data and give it all to google to keep it safe for us (which we do with money today). Blockchain developers are very smart and build defense in depth against attacks, there's a reason why Ethereum has tens of billions of USD stored on it.
There are protocols for transferring cash on Ethereum (LUSD, RAI) that you can use that no one, not even nation states spending billions of dollars can stop you from using.
The tradeoff is they won't scale to the world. But then there are less secure protocols (DAI, USDC) that do scale which will be fine for 99.9% of people (who aren't terrorists or being targeted by the government).
Tech is all about tradeoffs and you can learn about them from experts in the field rather than an obviously anti-crypto YouTube video to understand them.
All of these are far more censorship resistant than any banks or traditional financial services.
In regards to 51% attacks they aren't going to happen to Bitcoin or Ethereum.
For possible flaws, to put it in terms that technical non-crypto people understand, his arguments are like saying "well Heart Bleed happened and this could happen again thus all computers are unsafe and you can never trust them to be secure" which is technically true but that doesn't mean we should abandon storing our own data and give it all to google to keep it safe for us (which we do with money today). Blockchain developers are very smart and build defense in depth against attacks, there's a reason why Ethereum has tens of billions of USD stored on it.
There are protocols for transferring cash on Ethereum (LUSD, RAI) that you can use that no one, not even nation states spending billions of dollars can stop you from using.
The tradeoff is they won't scale to the world. But then there are less secure protocols (DAI, USDC) that do scale which will be fine for 99.9% of people (who aren't terrorists or being targeted by the government).
Tech is all about tradeoffs and you can learn about them from experts in the field rather than an obviously anti-crypto YouTube video to understand them.
All of these are far more censorship resistant than any banks or traditional financial services.