I think one of the biggest criticism of Bitcoin which comes with the very inherent flaw of it. I believe it was never designed in a way to be used by so many people. So the biggest problem it faces is the scalability issues, the moment you see a lot of on chain traffic immediately you will see the fees skyrocketing up, you will see slower transactions. Apart from this obviously the environmental impact of the Pow consensus is also a big criticism which a lot of pro environmentalists pose on bitcoin. So obviously the PoS or the hybrid solutions are becoming much more relevant to the overall situation in cryptos right now. and honestly I don't have any proper answers to the question on the scalability issues.