I disagree with how he expressed his opinion (doing an attack) about the whole Bitcoin getting centralized but I do agree to some extent that he is right, maybe right now it's not the case but in future the bigger pools will completely take control of the mining operation and then they'll make their own rules and that will again result in a non trustworthy blockchain and maybe these stress test are done by them to increase the miner's fee. I don't think this is how Satoshi envisioned the mining to be, I think it was meant to be completely decentralized and people mining from different parts of the world and not just from few mining farms.
It would have been better if mining would be non-profit in any other any way than just the sheer joy of running your own decentralised mining rig in your basement, as a hobby and as a means to keep the blockchain alive. You could make it break even, so no profit, but no loss, but it is still the market at work here.
The incentive is money, and that is one that feeds greed, greed is a very mighty thing and hard to control. We always want more, eat all the cake till nothing is left and then franticly search for the last crumbs...
Mining without profit would increase the decentralisation, because it would only interest those who want to invest without any earthly rewards other than recognition and being part of it. But where do you put the coins? How to distribute those? It is stil about the blockchain and the coins. To distribute them evenly around to all wallets available? That would make running the most wallets profitable and take the whole thing askew again.
Trying to manipulate the bitcoin value to keep it non-profitable for miners, but how?
It wouldn't work.
There was an altcoin with a dev who thought people would mine his coin for no reward whatsoever, apart from knowing they were keeping the network alive. It didn't work out. A few people mined it to begin with, but soon there were only a few hours a day when anyone was mining, and it became difficult to send coins to another wallet. Then the network was attacked, and the dev had to do a coin swap to a wallet with a different system that rewarded miners.