
Basically as the show went on and got more popular and mainstream in the uk, they had to censor a lot of it and also show less drama because of how bad the public treated the cast when the season (previous cast members have committed suicide) Also the UK airs on a public broadcast channel where they have to follow Ofcom regulations. While the US is now on Peacock, a streaming site which gives production a lot more freedom in what they can show.
Oh nothing major just the standard stuff like limiting the amount of alcohol per contestant, smoking banned completely now (first seasons of the UK let them do whatever), and a complete social media ban so family members and friends are not allowed to use the account on the contestants behalf