It's silly to pretend that they didn't influence and make music in the 80s because you want them to only exist in the decade they began. Their music changed, it shaped the 80s music. That's 80s. They were also 70s bands, and Pink Floyd began in the 60s. It doesn't change that what they came up with in the 80s was good.
Grind wanted desperately to "hate" all 80s music so he ignored what was good and pretended it came at some other time. But it didn't. There was much good 80s music. Better than all the disco wrapped into a huge sparkling ball. It may have sparkled, but that ball was made of poop.