You should probably open by defining what you're talking about. When most people talk about security, they are referring to how well defended from an attack they are - the first meaning of your thread title is that some aspect of the mathematical integrity of the blockchain or bitcoin has been broken. Yet the discussion that you link to is not talking about this at all, it is just one persons opinion on whether people are willing to pay for higher transaction fees, which is also not true. I've seen bitcoin transaction fees stay relatively low even when it has been priced even higher than it is now. That is because more computational power is added to the blockchain if it is economical to the local energy prices and there is profitability involved - which is often the case especially with new green energy sources coming online daily.