Why did you delete the older commands and values?

Hi! Why did you remove many commands and values in 1.13? I created a world with a lot of command blocks and redstone in 1.12.2 and now I must change they all because many commands were removed and the values are only words and no more numbers. And "blockdata" is easier than "data" with "merge" and "block".

Can you change it back, please? Thank you very much!

Btw, why spawn the bats now faster and in the free area too? It bothers me.