We all know that these additions to Bitcoin Core have slowed down transactions and made transactions more expensive.
Like Medusa has said they are not really addition to the Bitcoin core but something like a loophole that was first introduced by Casey something by adding images or additional datas to individual satoshis in the Blockchain.
Why are they being added when they make the network less efficient??
People benefit from its adoption. Many sell their NFTs while miners benefit from the higher fee. So yes ordinals are Supported by some and opposed by others, most me included admire it's creativity but feel it's just sacrificing long term benefit for short terms.
My understanding is that the block size has been increased from 1MB to 4MB to accommodate the additional storage.
No, they debate to do such is still ongoing. Bitcoin Block size is still 1mb. You missing it up with Segwit. Which is a soft fork that was created to improve the scalabilty of Bitcoin.
So you are saying that you think Ordinals and Runes are helping to make Bitcoin a better electronic cash system? The fee to get into the next block is now $6 US. This would make it cheaper to use Visa for transactions under $240US. And what about all of those stranded Sats. Sats in a wallet valued at less than $3-$6 US get stranded and never seen again.
I also don't understand how you can store Ordinals(NFTs) and Runes(fungible tokens) on-chain without increasing the storage required.