With this script, you can remove all tweets you are tweeted on Twitter. Don't forget add your nickname to line 9. (The script begins 60 seconds after pasting the code.)

twitter-remove-tweets.js

const timer = ms => new Promise(res => setTimeout(res, ms));

setInterval(async () =>
{
      // Get all tweets
      const allTweets = document.querySelectorAll('.css-1dbjc4n.r-18u37iz.r-1wbh5a2.r-13hce6t');

      // Filter tweets 
      const filteredTweets =  Array.prototype.slice.call(allTweets).filter(x => x.innerText === '@{YOUR_TWITTER_NICKNAME}'); // --> e.g. '@twitter'

      for (const tweet of filteredTweets) {
            tweet.scrollIntoView();
            // Click three dot and open action menu
            tweet.parentElement.parentElement.parentElement.parentElement.parentElement.querySelector('div[data-testid="caret"]').click();
            await timer(250);
            
            // Click delete button
            document.querySelector('.r-9l7dzd.r-4qtqp9.r-yyyyoo.r-1q142lx.r-1xvli5t.r-1rq6c10.r-dnmrzs.r-bnwqim.r-1plcrui.r-lrvibr').parentElement.parentElement.click();
            await timer(250);
            
            // Click confirm button
            document.querySelector('div[data-testid="confirmationSheetConfirm"]').click();
            await timer(250);
      }
      await window.scrollTo(0, document.body.scrollHeight);
}, 60000);

filteredTweets keeps coming out with length 0

I've set my user name at line 9 correctly

and checked allTweets which is populated with elements

and can see my username in innerText - but noticed innerText with name + date in differing formats

hence
const filteredTweets = Array.prototype.slice.call(allTweets).filter(x => x.innerText === '@{YOUR_TWITTER_NICKNAME}');

always has 0 in filteredTweets

so changed to use baseURI

const filteredTweets = Array.prototype.slice.call(allTweets).filter(x => x.baseURI === 'https://twitter.com/{myname}');

and worked your script worked and deleted all tweets

I noticed innerText would include my twitter name and the date - but the format was different from tweet to tweet

some were {name}\n{date}

some were {name}.{date}