[systemvoltage]

I am not a fan of Gov UK framework. For once, the banner takes up 50% of the space on my mobile browser.

All design elements and controls are excessively large and bloated. Negative space is liberally applied everywhere.

USWDS strikes a good balance.

[a2128]

You have to remember who this is being designed for - citizens wanting to use government services, who may not necessarily have great eyesight, great computer literacy or even literacy in general.

The last thing you should ever want is for someone to fail to apply for welfare benefits because they were overwhelmed by the website design.

I agree that the cookie banner could be smaller though.

[systemvoltage]

Yes, and USWDS does it without being bloated. Far more usable IMO.

There is room for well designed, compact UI that is also accessible. It is not that strict of a trade-off as you suggest.