Please note that the article headline is misleading. Twitter is not leaving or abandoning the EU. It will continue to be available as normal.
What happened is that the EU has a voluntary Disinformation Code that it has asked large companies to sign onto. A number of them agreed to the Code (Google, Microsoft, Twitch, TikTok...). The Code was essentially a series of guidelines and procedures that signatories agreed to self-enforce internally. Twitter was a signatory and has now decided to drop it.
There is no external authority that enforces the Code. There are no direct consequences for failing to enforce the Code. As the article says, there are a series of other, legally-binding, regulations on disinformation and content moderation that Twitter will need to adhere to.
Assuming you're not making this argument in bad faith (lol), why would private companies be any more trustworthy? They have every motivation to push whatever narrative their owners (read: advertisers) will pay for.
Of course they do, but doing your own research is the way to fix it, not suppressing a viewpoint you dont like. I should be able to say whatever i like as that is my choice. However, it is your choice whether or not to block me if you dont like my views