There are times when I'm required to write in Leftpondian and get caught out by the words that don't use -ize for -ise, like advertisement. I think the UK/US distinction has only become so definitive relatively recently and many people apply it overly rigidly, leading to mistakes like metre for meter.
Absolutely. Ize is the traditional, old-school, Shakespeare and Dickens, still-found-in-the-OED-as-preferred formation. Ise is the Johnny-come-lately variant, based on an incorrect assumption of a French derivation. Ize was in The Times' editorial style guide as the 'correct' form until about 30 years ago.
"It's American and therefore a terrible pollution of British purity" used to be the preserve of the green-inked letter to the editor. In a world where flat-Earthers, moon-landing deniers and antivaxers are on the rise, it's probably not surprising that angrily failing to grasp etymology and blaming the nonexistent problem on the Americans is on the rise too.
