not only google that lift the ban, twitter and facebook also lift the ban. I do think the main reasons is, cause crypto is started to be considered as an inovation and many people think crypto have a good use. People start understand that this is the new businesses and its wrong to just ban it just because you are afraid about it.
They've realized the bigger market that crypto can bring to their business so they need to removed this ban thing and start to allow crypto back
to the advertising business, maybe they are also planning to move forward and embrace the system and make a big use out of it.