Every generation and teen subculture likes to put the boot into baby boomers like me. I’ve been physically attacked by skinheads, verbally assaulted by right-wing intellectuals and mocked by millennials. But I never thought I would be subjected to the derision and verbal lashings of Generation Z. The ‘zoomers’ — that is, people born after about 1995 — have come up with a cutting and dismissive retort for older people: ‘OK boomer.