Elon Musk has fucked the world and switched over to the "x.com" domain from "twitter.com" for all platforms. Of course this screws up anyone who wants to paste tweets into posts.
WORKAROUND FOR NOW: Instead of just pasting the link in a post, use the Media button and paste the URL in there, BUT, before hitting Submit, change the "x.com" to "twitter.com" and the tweet will hotlink.
Keep in mind I'm doing all this on a PC, I haven't tried it on a phone or pad yet.