https://metro.co.uk/2024/09/23/x-twitter-set-make-huge-change-block-feature-21658952/
The block feature will prevent blocked users from engaging with you, but if you block anyone and/or they block you then you can still see each other's posts.
Possible legal implications- Along with almost no moderation, this would be in breach of the yet to be enforced online safety harms bill the UK passed. The Apple and Google app stores require social media apps to have a suitable block function for safety reasons.
As well as no longer being able to hide disturbing/violent/other content we may not wish to see, could this put women at harm by making it easier for stalkers?