Windscale was bad but it was at least three orders of magnitude less severe than Chernobyl in terms of radiation release.
Cockcroft had also insisted that the chimneys at Windscale be fitted with expensive scrubbing equipment, which everyone thought was idiotic until the fire. Not exactly "relaxed safety" there.
One dude insisting on one safety measure being added to a catastrophically stupid and unsafe design, while being resisted by everyone else, is very much within the realm of “relaxed safety.” In fact, I’d say that’s a rather mild and understated way to describe it. “Utterly negligent on safety” would be more accurate.
Cockcroft had also insisted that the chimneys at Windscale be fitted with expensive scrubbing equipment, which everyone thought was idiotic until the fire. Not exactly "relaxed safety" there.