They’re nearly empty now, those rusting silent behemoths overlooking the water at Harborplace, and all anyone can talk about is how they’re going to be demolished and replaced with something newer and more modern. John Pleyvak knows the nostalgia for the landmark won’t make sense if you didn’t see it before, when it was extraordinary. Bustling. Beautiful. “It’s a shell of itself,” said Pleyvak, who worked for years in the 1980s at Jean Claude’s, a celebrity-filled French restaurant in the Pratt Street Pavilion. “But back then, it was the place to be. It was on the cover of Time magazine. They said in the article that more people came through in the second year than Disney World.”