It's not blocked in the UK, nor is it because of the OSA.
They decided to withdraw from the UK market as the ICO (not OFCOM, who handle OSA) fined them for mishandling the PII of children, not under the OSA, but under UK’s Children’s Code[1] which is part of the DPA (UK implementation of GDPR into law)
They decided to withdraw from the UK market as the ICO (not OFCOM, who handle OSA) fined them for mishandling the PII of children, not under the OSA, but under UK’s Children’s Code[1] which is part of the DPA (UK implementation of GDPR into law)
[1] https://en.wikipedia.org/wiki/Children's_Code