[1] - https://www.legislation.gov.uk/ukpga/2023/50/section/55
[0] https://en.wikipedia.org/wiki/John_Gilmore_(activist)#Activi...
The smaller companies like 4chan are going to court to have the matter settled. If that is settled in 4chan's favour, legally the UK won't be able to do anything.
The UK being blocked from the outside won't happen anyway. The large tech giants will just either cut a deal (this already happen with Apple/iCloud), or they will comply with the new acts. The sites that don't comply won't be big enough for anyone to care in normie land and thus there will be no real pressure on the UK gov.