The blog post conflates several issues together:
(1) why is the blockchain still so inefficient?
(2) why is the blockchain still so lacking in practical use cases with widespread adoption?
I think she is totally fair in complaining about (1). Either it is impossible to have decentralization and efficiency or it's just a technical problem that will be solved given more time. I don't have the answer here - only time will tell.
For problem (2), I think it's mostly an over-exaggeration of the use case(s) where web3 that beats web2. As far as I can tell there is one and only one use case: web3 can do things while having a middle finger pointed at major governments. Web2 cannot. In that bitcoin and eth can offer people of Argentina a some reliable store of value (against their own currency which depreciates at 50% per year) it has generally achieved that. You can't even buy a Tesla in Argentina so the adoption of that wonderful technology there is zero.
To claim that it's the next web2 or mobile tech is both an exaggeration and an underestimate. Web3 will not be much of a challenge to web2 or mobile. Instead it will be a huge challenge to existing political, monetary and taxation systems. It will be the tool of the rich to evade taxes, for libertarians to evade control and for those living in high inflation countries to build wealth.
Those who complain that this is hardly revolutionary are both right and wrong.