How old is Cardano compared to Bitcoin? Maybe that's where he's coming from?
Cardano is more or less 6 years old as far as I know, so we could say that it's too "early" for Cardano. Compared to it's competitors though, some smart contract platforms are like half the age of Cardano but yet they all have those so called "apps" working already. Maybe Cardano is taking the sort of "play safe" approach in terms of development? Alright, that's probably a good strategy to prevent bugs and breaches and such. But him calling out Bitcoin for slow development LOL? Just disingenuous.
https://en.wikipedia.org/wiki/Cardano_(blockchain_platform)
The platform began development in 2015 and was launched in 2017 by Charles Hoskinson, a co-founder of Ethereum.
When it comes to development Cardano is #1 and bitcoin is not even in the top 10 list.
So Charles is exactly correct.
https://twitter.com/ProofofGitHub/status/1385624516127232003?s=20Cardano again is the top 1 in development activity on Github Discussion