This is by far the dumbest argument against PoS.

PoW is not permissionless either. Once a PoW coin gets big enough for ASICs to be profitable, then BAM- their permission cherry gets popped. You need to get permission from sellers of the coin, ASIC companies, or have millions of dollars around to develop your own ASIC. Even if it is the latter (or the latter latter), you need to get permission from a chip foundry.

Even still, the permission versus permissionless argument is further silly.

All cryptocurrencies, whether PoS or PoW, ultimately need permission from ISPs, regulatory bodies, and governments.

PoS coins have been around for over three years now. Throughout the entire history of PoS coins, there hasn't been a single instance where someone has not been able to become a stakeholder of any PoS coin if they wanted to. Permission has always been attainable. There is always someone looking to exit their position. Whether it be to invest in other alt coins, taking profits, sticking to their stop loss, needing FIAT for real world purchases, an unexpected expense or emergency, etc...

Furthermore, PoS coins are not inherently less anonymous. There are ways of getting ahold of coins that are quite anonymous, such as exchanges that do not enforce KYC policies, registering a burn account on a forum and purchasing coins through escrow, utilizing a VPN and/or TOR, and using an exchange on the deep web are all examples. And... I don't think you meant this, but after you have the coins, PoS cryptocurrencies can be just as anonymous as PoW cryptocurrencies, as the same anonymization techniques can be applied.

PoW is not any more decentralized either by any means. It may start off that way, but eventually all PoW cryptocurrencies tend towards centralization due to the economies of scale that ASICs bring. That is... if the are successful enough to get to that point, but who really wants to invest in a cryptocurrency that would be unsuccessful anyways?

Yet, this thread is not meant to be a PoW vs PoS debate. It intended to be a think tank as to different ways deflationary cryptocurrencies can be conceived, mainly as far as maintaining consensus. If you want to debate PoS v PoW, then I kindly ask you to start another thread, but all of this has been debated ad nauseum for years. You aren't bringing any new arguments to the table really, and a lot of people find the above arguments you bring up against PoS as not being a big deal- valid or not. IMO, most of them are not valid.

Here is why PoW is Permissioned, ( mined on a CPU or ASIC)
Facts
Permissions Required to generate a PoW Block if you Mine it
1.  Permission from the ASICS seller , to buy their ASIC.
2.  Permission from your local Govenment to allow the ASIC to be shipped to you.
3   Permission from the Electric Company to power your ASIC.
4.  Permission from the Mining pool you have to join because group mining is your only shot
5.  Permission from your ISP , so you have internet access to attempt to mine it.
6.  Permission from the original programmer thru the Open Source License granted so you can run the software.
If you pay someone else to mine it , You need their permission and acceptance of your currency.

Permissions Required if you just buy it. (Same for PoW & PoS)
1.  Permission from the Exchange
2.  Permission from the Seller

Free Faucet  (Same for PoW & PoS)
1.  Permission from the one running the faucet

Hopefully we can put that falsehood permissioned verses permissionless to rest , because nothing peeves me more that hearing the same lie more than once.
There are No Permissionless systems in crypto.