Ethereum becoming Self Deflationary is still a debate as we have miner mining more than being burned daily. Ethereum being burned on average are around 3000 Ethereum which is worth around $9.3 Million.
Self deflationary means that the supply of Ethereum will be burned which each mined block is not only reducing the total supply, furthermore, the reward for miners has decreased. Currently, Ethereum has an unlimited supply. What that means is that with each block more and more Ethereum is added to the supply.
However, with the London Hard fork that just happened a few days ago, a certain amount of Ethereum will be burned with every block, currently, about 3000 Ethereums every day. I still won’t call it deflationary because more Ethereum is being produced than being burned but this is still a huge step towards creating a supply shock which means that there will be less supply of Ethereum from now onwards than it used to be. Less supply with the same or high demand means the price is expected to go up in the long run. We can’t really tell what the price would do in short term because of market volatility and news.