True, though .uk is more correct (Great Britain doesn't include Northern Ireland) and is reserved by the United Kingdom in ISO 3166
Also, Ukraine got shafted into another mismatch (UA is TLD and ISO alpha-2, UKR is alpha-3), although in their case one could say the country wasn't around when ISO codes were formulated. Some Linux distributions used to have a UK keymap which was... ukrainian. That was a lot of fun to fix (not).