Public tech blogs and stuff like that was usually reserved for more senior members of the team. But reviewing code seems pretty standard in the UK for any decent software company from my experience.

It's never safe to have a single point of failure for code review. If all code goes through one guy then they can get lazy and not thoroughly check the code (I've done it myself when I've had a backlog). Sometimes a developer will just submit buggy code because they're lazy! Two lazy developers causes an issue in production. Code reviews need to be spread around the team fairly evenly.

Some developers may have more experience in certain areas, like a core library or service. In those cases it does make sense to have a final pass by a more specific developer. But initial code review passes can be done by anyone.

Pay and responsibilities in tech in the UK really depends on what part of the tech industry you're in. Start ups don't pay that well. Small businesses don't really pay well. Most medium to large businesses can pay fairly well depending on industry.