In my experience as of right now, some tags are blocked completely, and some tags you can access them if you have direct links. Just tested it to remind myself, as a US resident, the loli, or 'petite' as it was briefly called, tag is accessible through direct links (the tag won't be there anymore and you can't search for the tag, but it's obvious which ones used to have it), but the 'school' tag gets completely blocked.
As an example, despite having purchased the games and the characters definitely not being loli, if I go to my purchase history and try to access the page I can't see The Resurrected Exorcist Maiden, or Taimamiko Yuugi or any of Unko morimori maru's works, because the characters wear school girl uniforms.
If I check a page like Black Panda's however, I may only see the one game that didn't technically get tagged loli, but by using direct links I can access the page for the other games, because they are tagged for loli, but not for school. It's incredibly stupid and arbitrary, but it is what it currently is.
Visa and Mastercard do seem to be back as options in the checkout however. I haven't personally gotten them to work despite trying, but I suspect that's more a problem on the side of my card and it got blocekd as fraud, and I just can't be bothered to fix it when I have a working way to buy points.