Why don't my local magpies swoop?

hi all! I don't have any pics of this pair of magpies, but I can say with certainty that I've never seen them swoop. I've lived near them for at least 10 years in Sydney. And I do believe they're a mated pair as it's always two of them and never just the one. Not once have I been harassed. I've never interacted with them by feeding them etc, but my next door neighbour does, and has maintained a good relationship with them for years. I'm just really curious as to why this pair are seemingly the only ones I've never seen swoop. Are they infertile? Too old to have chicks? Do they have chicks but just rule me and the neighbourhood as innocent by association due to my next door neighbour being their friend? Could they be like some penguin species and they're gay? Do magpies even do same sex relationships? Those last two questions are mostly jokes, but honestly I've been scratching my head on this one.