This article is complete BS. Proof of Stake is more secure than Proof of Work for a simple reason. The cost of doing a 51% attack (to stop the blockchain or to start censoring specific transactions) on a PoS blockchain is exponential, whereas the cost of doing such an attack on a PoW network is linear. This is because as an attacker acquires more tokens, the price of remaining tokens increases exponentially as the attacker approaches the 50% mark. If the network is well decentralized in terms of token ownership, it may not ever be possible for the attacker to acquire 50% of tokens; also, their incentive to continue with the attack decreases as their stake in the blockchain increases. Unlike with PoS which requires the attacker to keep buying more (limited-supply) tokens, with PoW, ASIC miners don't become more expensive as the attacker gets closer to having 51% of the hash power; this is because the market will produce more ASIC miners to compensate for any increase in demand. The global supply of ASIC miners has no upper bound.
The article is also misleading in inferring that there is a very narrow range of ways to implement PoS; in reality, there are many ways and all of the 'drawbacks' mentioned only apply to certain (poorly designed) implementations which no modern PoS blockchain would ever use.
> What happens if you’re presented with two identical blocks, and have to decide which one to pick?
Easy, you can just have a vote on one of the block and choose the one with the majority votes; it can be chosen on the basis of any attribute of the block (E.g. commonly you can look at block IDs). This is what PoS blockchains like COSMOS do with the Tendermint protocol. Other blockchains like Lisk have a delayed voting so that consensus is reached after a certain number of blocks.
> The entire point of the consensus mechanism was to allow us to tell which transaction was first, without personally having seen it take place.
Anyone who understands distributed systems knows that the exact order of transactions (down to a few hundreds of millisecond) cannot be physically determined due to latency between the nodes and the unpredictable geography of participants. This is as true for PoW as it is for PoS. The most important thing (for certain use cases such as DeFi) is that transactions cannot be predictably front-run; using block ID ordering with voting as the basis for selecting between two valid blocks guarantees this. If the forger tried to cheat the system by producing multiple blocks, the network may not be able to reach consensus on the block vote and the forger would not receive any block rewards.