why he didn't just create a new social platform like that. It's not difficult even for a businessman to do it, but maybe because Twitter is in great demand by all circles.
You must visit elon's tweet and it's clearly stated the main reason why he bought twitter. Freedom of speech has become the main concern that makes elon tried to use billions of money. Remember that about the meme for trump will come back when twitter acqured by elon. Elon has been offering trump to come back to the twitter again but he was refusing elon's offer. There is also main reason like you can't compete with the big platform as big platforms will always have value on its name and many more.
I think that it's quite easy to know why elon was deciding to buy all of twitter shares.